Course Profile Science, Grade 10, Locally
Developed
Unit 2: Chemistry: Chemical Reactions and their Practical Applications
Time: 29 hours
Activity 1 | Activity 2
| Activity 3
Students investigate, through laboratory experiments, a variety of chemical reactions with an emphasis on the use of household and workplace chemicals and practical applications of their reactions. Acids and bases are studied in detail to provide knowledge about their properties and uses. Students demonstrate their understanding of the pH scale to identify acidic and basic properties of materials. Students are given opportunities to demonstrate the proper storage, handling, and disposal of chemicals and the products of reactions. Safety, inquiry skills, collaboration, and communication are emphasized in this unit.
Strand(s): Chemistry
Overall Expectations: CHV.01, CHV.02,
CHV.03.
Specific Expectations: CH1.01-.08,
CH2.01 A/B/C/D/E/F/G, CH3.01-.03.
|
Activity 1 |
Characteristics of Chemical Reactions |
630 minutes |
|
Activity 2 |
Acids and Bases |
690 minutes |
|
Activity 3 |
Chemistry in Our Everyday Lives |
420 minutes |
|
Task |
Type |
Title |
Time |
|
1.1 |
Learning/Explore |
Introduction to Lab Safety |
45 minutes |
|
1.2 |
Learning/Focus |
Introduction to Lab Procedures |
60 minutes |
|
1.3 |
Learning/Diagnostic |
Physical vs. Chemical Change Concept Attainment |
30 minutes |
|
1.4 |
Assessment |
Physical Change vs. Chemical Change Checklist |
30 minutes |
|
1.5 |
Learning/Observe |
Observing and Recording Characteristics of Chemical Reactions |
60 minutes |
|
1.6 |
Assessment |
Chemical Reactions: Concept Mapping |
30 minutes |
|
1.7 |
Learning/Diagnostic |
Cut and Paste Activity – Reactants and Products |
60 minutes |
|
1.8 |
Learning/Diagnostic |
Factors that Affect Reaction Rates |
60 minutes |
|
1.9 |
Assessment |
Rates of Chemical Reactions |
45 minutes |
|
1.10 |
Diagnostic |
Identifying Everyday Chemical Reactions |
30 minutes |
|
1.11 |
Assessment |
Chemical Reactions in the Real World |
60 minutes |
|
1.12 |
Summative Assessment |
Station-Based Activity |
120 minutes |
|
2.1 |
Learning/Focus |
Introduction to Acids and Bases |
60 minutes |
|
2.2 |
Learning/Diagnostic |
Sour vs. Bitter |
60 minutes |
|
2.3 |
Learning/Diagnostic |
Properties of Acids and Bases |
60 minutes |
|
2.4 |
Learning/Consolidate |
Acid/Base Discussion and Note Taking |
30 minutes |
|
2.5 |
Learning/Focus |
What is a Chemical Formula? |
30 minutes |
|
2.6 |
Learning/Focus |
The pH Scale |
30 minutes |
|
2.7 |
Learning/Apply |
Testing For Acids and Bases in Ten Consumer Products |
60 minutes |
|
2.8 |
Assessment |
pH Determination of Acids and Bases |
60 minutes |
|
2.9 |
Learning/Assessment |
Neutralizing Acids |
60 minutes |
|
2.10 |
Learning/Diagnostic |
What is a Salt? |
60 minutes |
|
2.11 |
Assessment |
Acid Rain |
60 minutes |
|
2.12 |
Summative Assessment |
Acid Rain Research Paper |
120 minutes |
|
3.1 |
Learning/Explore, apply |
Chemistry In Everyday Life |
30 minutes |
|
3.2 |
Assessment |
Chemical Reactions in Life |
30 minutes |
|
3.3 |
Learning/Apply |
Classification of Household Products |
30 minutes |
|
3.4 |
Assessment |
Acid, Base, or Salt? |
30 minutes |
|
3.5 |
Learning/Consolidate |
Guest Speaker |
60 minutes |
|
3.6 |
Assessment |
Careers in Chemistry |
45 minutes |
|
3.7 |
Assessment |
Safety Poster |
75 minutes |
|
3.8 |
Learning/Explore |
Introduction to Environmental Chemistry |
30 minutes |
|
3.9 |
Learning/Assessment |
A Closer Look at the Environment |
30 minutes |
|
3.10 |
Summative Assessment |
Chemistry and the Environment |
60 minutes |
The use of equipment, safe laboratory practices, and information learned about WHMIS in Grade 9 Science should be reviewed. Concepts dealing with physical and chemical changes are required from Grade 9 as well as a knowledge of elements and the Periodic Table.
Specific planning for each activity is described in the Teacher Facilitation section. However, the following preplanning would be helpful:
1. Experiments in Activities 1 and 2 have extensive equipment requirements. Check each task carefully.
2. Summative Station-Based Activity (Task 1.12) requires preplanning to assure that all required materials are available.
3. Task 2.12 requires preparation of a research paper. Preplan with teacher/librarian and book access to the computer lab for access to the Internet.
4. Guest speaker requires preplanning for Task 3.5.
5. Tasks 3.6, 3.7, and 3.8 require preplanning with teacher/librarian or booking computer time to research on Internet.
6. Please take note of safety guidelines for the chemicals used in the teacher facilitation and the Appendices (student worksheets).
|
|
Strategy |
Description |
|
Activity 1 |
Concept attainment, concept mapping, inquiry/experimental |
Concept attainment is used to help students to distinguish between chemical and physical change. Inquiry and experiments are used to further identify differences between the two changes. Factors affecting reaction rates are investigated through several experiments. The culminating Station-Based Activity involves both experiments and research. |
|
Activity 2 |
Inquiry/experimental, discussion, research |
Experiments are used to help students identify properties of acids and bases. Teacher-led discussion solidifies student knowledge. Inquiry is used to explore the properties of pH, neutralization, and salt production. Students conduct independent research into acid rain and its effect on the environment. |
|
Activity 3 |
Inquiry/experimental, guest speaker, research |
Students use knowledge from the previous activity and conduct experiments to identify substances as acids, bases, or salts. Use of a guest speaker explores the various options of careers in chemistry. Environmental chemistry becomes the focus of a research paper done by students. |
|
Task |
Expectations |
Tool |
Assessing |
Who |
|
1.1 |
CH2.01A, CH2.01C |
Worksheet Answer Key |
Knowledge |
Student |
|
1.2 |
CH2.01A, CH2.01C |
Worksheet Answer Key Lab Safety Checklist Lab Procedures Rubric |
Knowledge, Inquiry |
Teacher |
|
1.3 |
CH1.01, CH2.01F |
Worksheet Answer Key |
Knowledge, Communication |
Teacher |
|
1.4 |
CH1.01 |
Worksheet Answer Key |
Knowledge, |
Teacher |
|
1.5 |
CH1.01, CH1.02, CH2.01A, CH2.01C, CH2.01F |
Worksheet Answer Key Lab Safety Checklist Lab Procedures Rubric |
Knowledge, Communication, Inquiry |
Teacher |
|
1.6 |
CH1.02 |
Concept Map Checklist |
Knowledge |
Teacher |
|
1.7 |
CH1.04 |
Worksheet Answer Key |
Knowledge |
Teacher |
|
1.8 |
CH1.03, CH2.01A, CH2.01C, CH2.01F, CH2.01G |
Worksheet Answer KeyLab Safety Checklist Lab Procedures Rubric |
Knowledge, Inquiry, Communication |
Teacher |
|
1.9 |
CH1.03 |
SLL Rubric |
Knowledge, |
Teacher |
|
1.10 |
CHV.01, CHV.02, CH3.01, CH3.02 |
Worksheet Answer Key |
Knowledge, Inquiry, Making Connection |
Teacher |
|
1.11 |
CHV.01, CHV.02, CH2.01F |
Reading for Understanding Rubric |
Knowledge, Communication |
Teacher |
|
1.12 |
CHV.02, CH1.01 |
Worksheet Answer Key |
Knowledge, Inquiry |
Teacher |
|
2.2 |
CH1.05, CH1.06 |
Worksheet Answer Key |
Knowledge |
Teacher |
|
2.3 |
CH1.05, CH2.01A |
Worksheet Answer Key |
Knowledge, Inquiry |
Teacher |
|
2.4 |
CH1.05 |
No assessment |
|
|
|
2.5 |
CH1.05 |
Worksheet Answer Key |
Knowledge |
Teacher |
|
2.6 |
CH1.05, CH1.06 |
Worksheet Answer Key |
Knowledge |
Teacher |
|
2.7 |
CH1.06, CH2.01A, CH2.01C, CH2.01F |
Worksheet Answer Key Lab Safety Checklist Lab Procedures Rubric |
Knowledge, Inquiry, Communication |
Teacher |
|
2.8 |
CH1.06, CH1.07, CH2.01A, CH2.01C, CH2.01F |
Worksheet Answer Key Lab Safety Checklist Lab Procedures Rubric |
Knowledge, Inquiry, Communication |
Teacher |
|
2.9 |
CH1.08, CH2.01A, CH2.01C, CH2.01F |
Worksheet Answer Key Lab Safety Checklist Lab Procedures Rubric |
Knowledge, Inquiry, Communication |
Teacher |
|
2.10 |
CH1.08, CH2.01A, CH2.01C, CH2.01F |
Worksheet Answer Key Lab Safety Checklist Lab Procedures Rubric |
Knowledge, Inquiry, Communication |
Teacher |
|
2.11 |
CH1.05, CH2.01F |
Reading for Understanding Rubric |
Knowledge, Communication |
Teacher |
|
2.12 |
CH1.05 |
Research Paper Rubric |
Knowledge |
Teacher |
|
3.2 |
CHV.03 |
Comic Strip Checklist |
Knowledge |
Teacher |
|
3.3 |
CH3.01 |
Worksheet Answer Key |
Knowledge |
Teacher |
|
3.4 |
CH3.01 |
Worksheet Answer Key |
Knowledge |
Teacher |
|
3.6 |
CH2.01D, CH2.01E, CH3.03 |
Teacher-created Checklist |
Knowledge, Communication, Making Connections |
Teacher |
|
3.7 |
CH2.01D, CH2.01E, CH3.02, CH3.03 |
Poster and Presentation Rubric |
Knowledge, Communication, Making Connections |
Teacher |
|
3.8 |
CH2.01D |
Worksheet Answer Key |
Knowledge |
Teacher |
|
3.9 |
CH2.01D, CH3.02 |
SLL Rubric |
Knowledge, Making Connections |
Teacher |
|
3.10 |
CH2.01B, CH2.01D, CH2.01E |
Research Paper Rubric |
Knowledge, Communication |
Teacher |
Ritter, Bob, et al. Nelson Science 10. Toronto: ITP Nelson, 2000. ISBN 0-17-607501-1
Grace, Eric, et al. SCIENCEPOWER™
10. Toronto: McGraw-Hill Ryerson Limited, 2000.
ISBN 007-560-363-2
Shapiro, B et al. Chemistry at Work. Pearson Education Canada, 1989. ISBN 0-7730-4730-1
ITP Nelson Website – http://www.nelson.com/nelson/science
Periodic Table Site – http://pearl1.lanl.gov/periodic/
Eisenhower National Clearinghouse – http://www.enc.org – Source of teaching resources
Canada’s Schoolnet – http://www.schoolnet.ca – Source of lesson plans, labs, demos, classroom activities, assessment tools, performance indicators and background resources.
See web sites identified in Unit 5 (Culminating Activity) dealing with acid rain.
Encore Software. Science Advantage 2000: CD-ROM. Remedial. Provide interactive activities and self-paced study.
DK Multimedia: Super Tutor Learning Networks, High School Science-Chemistry, Biology, Physics: CD-ROM. Provided online homework help, lesson plans
Microsoft: Microsoft Encarta Deluxe 2000. CD-ROM. Current information source.
Bill Nye Video – Acids and Bases
(available at most School Board Resource Centres) or from Magic Lantern
Communications, 10 Meteor Dr., Toronto, ON M9W 1A1
1(800)263-1717; e-mail – video@magiclantern.ca; web site – www.cbc.ca
(Teachers are reminded to follow all copyright regulations when showing videos)
Time: 630 minutes
Students demonstrate an understanding of chemical reactions through hands-on investigations of everyday chemicals in the home, lab, and workplace. These investigations also lead into lab activities that demonstrate the factors that can change the rates of reactions. The difference between chemical and physical changes is underlined through these investigations. Students also use word equations to describe the reactions covered in this activity. An emphasis is placed on lab safety, and the safe use of glassware, Bunsen burners, chemical usage, and the safe disposal and clean up of a lab.
Strand(s): Chemistry
Overall Expectations
CHV.01 – demonstrate an understanding of chemical reactions;
CHV.02 – investigate reactions of different types of everyday chemicals.
Specific Expectations
CH1.01 – demonstrate an understanding of the differences between chemical and physical changes;
CH1.02 – describe the characteristics of simple chemical reactions (e.g., synthesis, decomposition, oxidation);
CH1.03 – identify the factors that can affect the rate of chemical reactions (e.g., temperature, surface area, concentration of chemicals...);
CH1.04 – demonstrate an understanding of chemical reactions using word equations;
CH2.01A – demonstrate knowledge of safety procedures when carrying out investigations in the laboratory using materials, tools and equipment to carry out chemical reactions (e.g., wear safety glasses, use care when heating materials, follow WHMIS guidelines and emergency procedures, use proper procedures for handling, storage and disposal of chemicals);
CH2.01C – demonstrate the skills required to investigate chemical reactions, using instruments, tools, and apparatus safely, accurately, and effectively (e.g., evaporating water in a neutralization reaction to recover salt; determining the properties of acids and bases; simple synthesis, decomposition and oxidation reactions);
CH2.01F – communicate scientific ideas, procedures, results, and conclusions about chemical reactions using appropriate language and formats (e.g., sharing in small groups, demonstrations, structured lab reports);
CH2.01G – investigate, by laboratory experiment or classroom demonstration, factors that can affect the rate at which chemical reactions occur.
1. Most experiments require general laboratory equipment, such as test tubes, beakers, retort stand and clamp, Bunsen burners, and graduated cylinders.
2. Station-Based Activity (Task 1.12) involves 6 different stations. Check the requirements for each station carefully.
Equipment required for Task:
· 1.2 – mothballs, vinegar, baking soda
· 1.5 – ammonium chloride, baking soda, vinegar, magnesium ribbon, copper(II) sulfate, iron filings, phenolphthalein, calcium hydroxide, tarnished penny, table salt, sugar, sodium phosphate, silver nitrate
· 1.8 – vinegar, carbon (powdered form), corn starch (demonstration)
· 1.10 – chart paper, markers, various print sources dealing with different types of chemical reactions
· 1.11 – selected/adapted short articles that focus on the chemistry behind everyday chemical reactions in the real world
· 1.12 – copper(II) sulfate, sodium hydroxide, copper wire, silver nitrate, baking soda, vinegar, dilute (less than 0.01 M) hydrochloric acid, candle
Safe lab practices and procedures are reviewed at the start of this activity. Building upon learning covered in the Grade 9 Essential Science document will lead the students into this activity. Students build upon the concepts covered when studying physical and chemical change and extend this knowledge to lab explorations that identify the characteristics of both chemical and physical reactions.
Students participate in a scavenger hunt activity focusing on the location and the functions of lab and safety equipment that they will be using throughout the course.
Teacher Facilitation
1. Lead a class discussion on the types of lab facilities found throughout society (e.g., environmental, medical research, engineering, nutrition, quality control, applied research). Lead students in a discussion to develop a board chart of types of labs and investigations carried out in each (e.g., testing of pH of rainwater in an environmental lab; how fast metals rust in a quality control lab; fat content of foods in an applied research lab). Have students copy this table into their notebooks.
2. Prepare a scavenger hunt recording worksheet so the students can clearly record the location and use of the lab and safety equipment. Appendix 2.1 provides a sample worksheet, which may be customized for your classroom/lab.
3. Organize the scavenger hunt in which the students locate and record where equipment is located throughout the room. Display school lab and safety equipment and lead a discussion about their names, functions, and proper way to use them (e.g., hardware, glassware, safety goggles, eyewash station, broken glassware/solid waste containers, fire blanket).
Assessment
Students can self-assess and peer-assess the worksheet a using teacher-created answer key.
Accommodations
The function and proper use section of the scavenger hunt recording worksheet can be designed as a matching and/or describing exercise on the worksheet (e.g., table format) to accommodate for students with poor memory and/or literacy skills.
Students carry out a simple lab that will focus on lab procedures, correct equipment usage, safe handling of chemicals, and effective observation/recording skills. Students become familiar with following lab steps, equipment storage and use, safe handling of chemicals, and record their observations in prepared charts.
Teacher Facilitation
1. Introduce to students the Lab Safety Checklist (Appendix 2.2) and Lab Procedures Rubric (Appendix 2.3).
2. Lead students through “Fizzy Pop Lab” (Appendix 2.4) and familiarizing students with correct lab procedures.
[Note: The rising and falling of the mothballs in the baking soda and vinegar solution is attributed to the gas being evolved from the reaction. The bubbles rise to the surface, carring the mothballs with them; the bubbles are lost and the mothballs fall again. Emphasis should be placed on the fact that the gas evolved in the solution causes the “fizz” sound that is heard in the solution.]
Safety Precautions
Students must wear safety goggles throughout this lab activity. Waste liquid should be disposed of using a waste bottle. Glacial acetic acid should not be used for this, or any other activity, covered in this course outline. Use household vinegar as a substitute.
Use the following protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Disposal: Follow federal, provincial, and local guidelines.
The following MSDS (Materials Safety Data Sheets) information is provided:
Vinegar: Do not use glacial acetic acid in this activity. Use household vinegar.
Napthalene (mothballs): Keep mothballs away from sources of heat. Use a waste disposal jar to dispose of used mothballs.
Assessment
Assess student work using a worksheet answer key. Assess lab work using Lab Safety Checklist (Appendix 2.2) and Lab Procedures Rubric (Appendix 2.3)
Accommodations
Enlarge print for students with poor vision. Use scribe and/or peer helper, tape recorder, or computer as an alternative to recording observations in this activity.
Students take part in a concept attainment or sorting activity on the concept of physical vs. chemical change and participate in a teacher-led discussion on the differences between the two types of changes. Students complete a worksheet on physical and chemical changes (Appendix 2.5).
Teacher Facilitation
1. Develop the concept of physical and chemical change by providing students with pictures of both types of changes. Students sort these pictures into two categories: physical change and chemical change.
2. Lead a discussion on the characteristics of physical and chemical change by asking the students to summarize the key points demonstrated in the sorting activity. [Note: Characteristics of physical change include: altering only the form of a substance; physical changes are reversible; changing of state, magnetizing, and dissolving are examples of physical change; the chemical composition of substances are not changed in physical changes. Characteristics of chemical change include: production of a new product; production of heat, light, gas, or precipitate; colour change.]
Assessment
Make diagnostic assessment using a teacher-created answer key.
Accommodations
Group work will facilitate the review of the concepts of physical and chemical changes. Use of chart paper, markers, and defined roles for the group members (scribe, idea producer), will collectively allow for quick review of the required concepts. Possible arrangement: Think/Pair/Share (Appendix OV-4) for students with weaker abilities.
Students complete worksheet identifying physical and chemical changes.
Teacher Facilitation
1. Prepare worksheet describing a variety of situations which students identify as either physical or chemical change and explain why (e.g., pulverizing stone is a physical change because the stone has not changed, it has become smaller pieces; baking bread is a chemical change because a new compound has formed. See Appendix 2.6.
2. Clarify for the students the background of some of the changes with which they may be unfamiliar (e.g., dry cleaning, dry ice in water)
Assessment
Assess using a worksheet answer key.
Accommodations
Provide a peer helper/scribe to assist with writing.
Students carry out a series of experiments and observe and record their characteristics in chart form.
Teacher Facilitation
1. Prepare worksheet for experiment that identifies evidence of chemical change. See Appendix 2.7.
2. Review Lab Safety Checklist (Appendix 2.2) and Lab Procedures Rubric (Appendix 2.3) and familiarize students with their use. Identify to the students the lab safety warnings that should be followed in this lab.
3. Solutions of copper(II) sulfate, ammonium phosphate, silver nitrate and calcium hydroxide should be prepared ahead of time and should be ~0.01M
4. Some of the reactions in the experiments described below may be classified as decomposition (the breakdown or destruction of a substance into simpler substances), synthesis (putting together or combining of two or more substances to form a more complicated substance) or oxidation (the linking of oxygen with another substance).
5. Students carry out a series of experiments and obtain the following information:
a. Ammonium chloride (1 g) in 1-2 cm of water in a test tube causes a significant decrease in temperature. [Note: Change in temperature occurs.]
b. Copper(II) sulfate solution poured on iron filings causes an immediate change in the iron filings. The surface of the iron is replaced by copper. [Note: Colour change and temperature change occur.]
c. Sprinkle a little table salt on a tarnished penny in a watch glass. Add enough vinegar to cover the coin, and let stand for one minute. Wash off and dry the penny. Students observe that the tarnish has been removed and bright, shiny penny is left. [Note: Colour change occurs.]
d. Burn a small piece of
magnesium. Do not look directly at magnesium while it is burning.
[Note: Heat, light, and gas are produced.]
e. Baking soda is added to vinegar. [Note: Gas is produced.]
f. Teacher Demonstration: Mix 1 mL of sugar and 1 mL of baking soda together. Heat the mixture in a test tube with a supporting test tube clamp/retort stand. Have students observe and record the reaction.
g. Students conduct investigations where precipitates are formed. Students put a small amount of sodium phosphate (Na3PO4) into a test tube. Record the appearance of the sodium phosphate.
h. Add silver nitrate (AgNO3) solution, drop by drop, to the test tube. The silver nitrate solution should be in dropping bottles. Record the appearance of silver nitrate.
i. Record the number of drops needed to produce a white precipitate.
j. Students obtain 2 mL of phenolphthalein and calcium hydroxide(aq) in separate test tubes. Record the appearance of the phenolphthalein and the calcium hydroxide(aq). Add the phenolphthalein to the calcium hydroxide and record the appearance of the precipitate in chart form. Students should be given the definition of a precipitate - a solid insoluble material that forms in a liquid as a result of a chemical reaction between two soluble substances.
Safety Precautions
The MSDS (Materials Safety Data Sheets) have provided the following information on the chemicals used in this experiment:
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Disposal: Refer to federal, provincial, and local guidelines.
Ammonium chloride: Use microamounts when used. Dispose of ammonium chloride using a
waste disposal jar. [Note: Empty containers can have residues, gases, and mists and are subject to proper waste disposal.]
Calcium hydroxide: Use microamounts when using. Caustic irritant to eyes, skin, and respiratory tract. Use a waste disposal jar.
Copper(II) sulfate: May cause skin irritation. This substance has caused reproductive and fetal effects in animals. Use a waste disposal jar.
Magnesium: Do not look directly at burning magnesium. Ensure that the lab is well ventilated.
Phenolphthalein: Use microamounts when using. Use a waste disposal jar.
Silver nitrate: Use microamounts when using. Danger! Strong oxidizer! Contact with other materials may cause a fire. Causes skin burns. Use a waste disposal jar.
Sodium phosphate: Use microamounts when using. Use a waste disposal jar.
Assessment
Assess student work using a worksheet answer key. Assess lab work using Lab Safety Checklist (Appendix 2.2) and Lab Procedures Rubric (Appendix 2.3).
Accommodations
Allow more time for completion of experiment by students with poor motor skills.
Students prepare a concept map with the central topic being chemical reactions. The connectors and descriptors are provided to facilitate the production of a complete concept map.
Teacher Facilitation
1. Introduce the arrangement of a simple concept map using TV as an example. (See Appendix 2.8 – What is a Concept Map?). A concept map is a diagram that indicates the relationships between other concepts in a meaningful framework. See Appendix 2.9 for a more elaborate sample of what a concept map looks like.
2. Provide the students with a prepared list of connectors and descriptors based upon the past tasks covered in this activity. Hand out a sheet of blank paper and have them complete a graphic organizer on chemical reactions.
3. The framework of connectors and descriptors is as follows:
|
Descriptor (Subordinate concepts) |
Connector (Statements which link the Descriptors) |
|
reactants |
involve |
|
products |
becoming |
|
irreversible |
are |
|
heat production |
and are characterized by (Used five times.) |
|
light production |
an example would be: (Used five times.) |
|
gas production |
produce |
|
colour change |
which have |
|
precipitate forming |
|
|
burning wood |
|
|
baking soda and vinegar |
|
[Note: Additional words may be added here.]
|
rusting metal |
|
|
cigarette burning |
|
|
sour milk |
|
|
new substances |
|
|
new properties |
|
Assessment
Use the Concept Map Checklist (Appendix 2.10) to assess the completed Chemical Reactions concept map.
Accommodations
Students are provided with a peer helper to assist them in completing the concept map. A Shape Only concept map could also be provided to facilitate the end concept map as well.
Students cut and paste reactants and products from past experiments and arrange the components into a table that is divided up into products and reactants. Reference for this activity is Task 1.5.
Teacher Facilitation
1. Review with students the fact that reactants are what was started with and products are what is created or what the reactants become. Relating the reactants to the start and products to the finish is an effective analogy.
2. Task 1.5 involved six specific experiments. The reactants and products for each are as follows:
|
Experiment |
Reactants |
Products |
|
ammonium chloride + water |
ammonium chloride(s) + water(aq) |
ammonium chloride(aq)* + water + decrease in temperature |
|
copper(II) sulfate + iron filings |
copper(II) sulfate(aq) + iron filings (s) |
iron sulfate(aq) + copper(s) |
|
tarnished penny + salt + vinegar |
tarnished penny + salt + vinegar |
shiny penny + salt + vinegar |
|
magnesium + oxygen |
magnesium + oxygen + heat |
magnesium oxide (white ash) + heat + light |
|
baking soda + vinegar |
baking soda + vinegar |
baking soda(aq) + water + gas |
|
sugar + baking soda |
sugar + baking soda + heat |
heat + light + gas |
* (aq) refers to the fact that the material is dissolved in water –
i.e., an aqueous solution
3. Utilize Appendix 2.11 for the cut and paste activity.
Assessment
Assess student work using worksheet answer key.
Accommodations
Think/Pair/Share (Appendix OV-4) approach can be used to accommodate students having difficulty with the task, or those who missed the lab (Task 1.5).
Students, working in pairs, observe and record the factors that affect reaction rates (dilution, surface area, and temperature).
Teacher Facilitation
1. Introduce the activity by carrying out a teacher-led discussion on what a “rate” refers to in chemistry. An excellent demonstration is the use of corn starch. Corn starch will burn slowly when it is placed in a small pile on a fireproof pad. Sprinkling a small amount of the powder in a Bunsen burner flame shows in a spectacular fashion how chemicals, when subjected to different conditions, have different reaction rates.
2. Prepare worksheet for dilution and surface area experiments (See Appendix 2.12). Worksheet will include space to record student observations.
3. Gather material for experiments described below:
The Effect of Dilution –
Vinegar/Baking Soda Experiment
1. Students prepare four different dilutions of vinegar solutions. In four test tubes, place the following amounts of water and vinegar according to the table:
|
Tube No. |
Volume Water (mL) |
Volume Vinegar (mL) |
Total Volume of Solution (mL) |
Proportion of Vinegar (or Concentration) |
|
1 |
5 |
1 |
6 |
1/6 or 0.17 |
|
2 |
11 |
1 |
12 |
1/12 or 0.083 |
|
3 |
17 |
1 |
18 |
1/18 or 0.055 |
|
4 |
23 |
1 |
24 |
1/24 or 0.042 |
Place a stopper in each test tube and invert it to mix the water and vinegar.
2. Students obtain four 50 mL beakers and place 1 g of baking soda in each beaker.
3. Students observe and time how long each reaction carries through as the different concentrations of vinegar are added to their baking soda samples.
4. Graph the results using a spreadsheet with Concentration of Vinegar on the x-axis (most to least concentrated) and Time (seconds) on the y-axis. Examples of graphing programs that could be utilized are: Excel, Appleworks, Corel Quattro Pro, or Microsoft 2.0. Each program has a tutorial to guide students in producing spreadsheets.
The Effect of Surface Area on Rates of
Reaction
1. Students obtain a small amount of powdered carbon and heat the sample in a deflagrating spoon in a Bunsen burner flame. Observations are recorded in chart form.
2. Students obtain a small amount of powdered carbon and sprinkle the carbon into the flame. Observations will be recorded in chart form.
3. Relating this experiment to the “sparklers” that are used during Canada’s Birthday will be an easy connection.
The Effect of Temperature on Rates of
Reaction
1. Students obtain a small amount of sugar and place it in a glass evaporating dish. Observations of the appearance of the sugar are made in chart form.
2. Students transfer the sugar sample to a deflagrating spoon. A Bunsen burner is lit according lab safety protocol. The deflagrating spoon with the sugar sample is placed in the flame and observations are made in chart form.
3. Relating how temperature increases the breakdown of sugar can be made using a comparison of the observations that are made in chart form.
Safety Precautions
Use a small amount of corn starch and utilize a fume hood so as to prevent contamination of the lab. Students must follow safe lab procedures when using the Bunsen burners.
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling
Disposal: Refer to federal, provincial and local guidelines.
The following MSDS information is provided:
Corn starch: Use microamounts when carrying out the demonstration. Use a fume hood to eliminate dust contamination.
Vinegar: Do not use glacial acetic acid for this activity. Use household vinegar. Vinegar can be flushed down the drain with excess water.
Baking soda: Use microamounts when using. This chemical released into the environment will not have a significant impact.
Carbon: Use carbon in a well-ventilated area. Use protective equipment as indicated. Sweep up material and place in a suitable disposal container if spilled.
Assessment
Diagnostic assessment using worksheet answer key. Assess lab work using Lab Procedures Rubric (Appendix 2.3) and Lab Safety Checklist (Appendix 2.2).
Accommodations
Pair students with appropriate ability level. Use peer helpers when available.
Students complete a Science Learning Log (SLL) entry using directed vocabulary from past activities and experiments involving Rates of Chemical Reactions.
Teacher Facilitation
1. Prepare a Science Learning Log worksheet with vocabulary (concentration, surface area, product, reactant, temperature) and focus questions (e.g., “How does the speed of a reaction change as the concentration increases?....temperature increases?...surface area increases..?”) Assign connections questions (e.g., “Why does food cook faster at higher temperatures?” of “If you want to cook pasta faster, would you use a big pot or a small pot?”).
Assessment
Assess SLL entry using SLL Rubric (Appendix OV-3).
Accommodations
Provide a peer helper to assist in completion of SLL entry. Allow students to dictate responses to a scribe or tape recorder.
Using printed media sources (magazines, newspapers, etc.) students brainstorm and record in chart form, different types of chemical reactions.
Teacher Facilitation
1. Place students in groups of three and provide chart paper and markers for recording their examples.
2. Teacher or students collect pictures or old magazines and choose pictures for the activity.
3. One student is recorder, one cuts out pictures of chemical change, and the third student brainstorms examples of chemical change.
4. Outline
the five characteristics of a chemical reaction to aid in this assignment.
[Note: Characteristics of chemical change are: heat given off, light
produced, colour change, gas production, and formation of a precipitate.]
5. The framework of the chart will be as follows:
|
Real World Area |
Reaction |
|
Cleaning |
|
|
Hospital |
|
|
Auto Repair Garage |
|
|
Restaurant |
|
|
Logging |
|
[Note: Additional examples may be added here.]
|
Cook |
|
|
Painter |
|
|
Custodian |
|
6. Chemical reaction examples should be characterized by simple terms. See Activity 1.5 for definitions of decomposition, synthesis, and oxidation. Clearly identifying the products and the reactants is not necessary.
Assessment
Diagnostic assessment using worksheet answer key.
Accommodations
Arrange group members so that mix is appropriate to the ability level of the students.
Students select a reading article and answer specific questions on the chemistry behind everyday reactions in the real world.
Teacher Facilitation
1. Select/adapt several articles (see Appendix 2.13) that focus on the chemistry behind everyday reactions. Articles could concentrate on such examples as cooking/baking, bleaching hair, oxidation of paint, and fermentation.
2. Students carry out a “Reading for Understanding” assignment and identify key points from their chosen articles through a question and answer format.
Assessment
Assess using Reading for Understanding Rubric (Appendix 2.14).
Accommodations
Enlarge print for students with poor vision. Use scribe and/or peer helpers, tape recorder, or computer as alternative to written response. Allow students to respond orally.
Students carry out a station-based assessment task that involves six different stations. Each station revisits tasks that were covered in this activity.
Teacher Facilitation
1. Prepare worksheet for Station-Based Activity. Worksheet should include spaces to record student observations and address specific conclusions that can be made from each station (Appendix 2.15).
2. Introduce the activity. Group students into pairs (lab partners) to complete the following investigations: lab safety/equipment identification, physical change vs. chemical change identification, lit candle chemical change observation, copper wire in silver nitrate experiment, baking soda + vinegar in a balloon experiment, Reading for Understanding assignment (baking bread).
3. Students gather the data for this lab in pairs, but work on the conclusions separately. This method ensures proper summative assessment.
4. Gather material for experiments described below.
Station 1: Lab Safety/Equipment Identification
1. Place a number of pieces of equipment out at this station and number them using masking tape. Each number corresponds to the equipment that is identified.
2. Included at this station is a Cloze worksheet that identifies the safety equipment throughout the lab room.
Station 2: Physical Change vs. Chemical Change Lab
1. Students place anhydrous copper(II) sulfate in water and record their observations. Inferences are made as to whether this is a physical or chemical change.
2. Students place a small sample of steel wool (previously cleaned with alcohol to degrease it) in a copper(II) sulfate solution and record their observations. Inferences are made with regards to this being a physical or chemical change.
3. Students place copper(II) sulfate in a sodium hydroxide solution and record their observations. Inferences are made as to whether this is a physical or a chemical change.
4. Students place a small magnesium sample in dilute (less than 0.01M) hydrochloric acid and record their observations. Inferences are made in regards to this being a physical or chemical change.
Station 3: Candle Observation
Students light a small candle and make all observations with regards to the characteristics of both physical and chemical change.
Station 4: Precipitate Experiment
Students obtain a piece of copper wire and place it in a silver nitrate solution. Observations are made with regards to this precipitate experiment.
Station
5: Baking Soda/Vinegar in a Balloon
Experiment
Students obtain baking soda and vinegar and place these substances into a balloon. Observations are made on this gas producing reaction.
Station 6: Reading for Understanding (Baking Bread)
Provide a Reading for Understanding article on baking bread and how this is a chemical reaction. An attached Cloze worksheet will assist students in identifying the chemical changes involved in this process.
Safety Precautions
Use care in handling solutions, especially the silver nitrate, acids, and bases. Wear safety glasses and take precautions around the candle flame.
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Disposal: Refer to federal, provincial, and local guidelines
The following MSDS information is provided:
Copper wire: Use microamounts when using. Dispose of in a waste disposal jar.
Silver nitrate: Danger! Strong oxidizer! Contact with other materials may cause a fire. Causes skin burns. Dispose of using a waste disposal jar.
Baking soda (sodium bicarbonate): Use microamounts when using.
Vinegar: Do no use glacial acetic acid. Use household vinegar. Vinegar may be flushed down the drain with excess water.
Assessment
Assess using a worksheet answer key for the station-based work. Assess the lab performance using the Lab Procedures Rubric (Appendix 2.3).
Note: Since this is a summative assessment, it is important that each student is graded independently.
Accommodations
Provide a peer helper to assist in carrying out lab and recording data.
See Resources for the unit.
Time: 690 minutes
Students become familiar with the properties of acids and bases and are able to identify common acids and bases by their chemical formulae and common names. The pH scale is used in conjunction with pH and litmus paper to test common substances for their acidic/basic properties. Knowledge and lab activities on this topic are extended to the neutralization process and the formation of salts by acids reacting with bases to form water and salts.
Strand(s): Chemistry
Specific Expectations
CH1.05 – state the properties of acids and bases and identify some common acids and bases by their common names and chemical formula (e.g., sulfuric acid, hydrochloric acid, nitric acid, sodium hydroxide, calcium hydroxide...);
CH1.06 – classify some common household materials as acids and bases;
CH1.07 – explain how the pH scale is used to identify acids and bases;
CH1.08 – describe the neutralization process, the formation of salts and identify some common salts by their formula;
CH2.01A – demonstrate knowledge of safety procedures when carrying out investigations in the laboratory using materials, tools, and equipment to carry out chemical reactions (e.g., wear safety glasses, use care when heating materials, follow WHMIS guidelines and emergency procedures, use proper procedures for handling, storage and disposal of chemicals);
CH2.01C – demonstrate the skills required to investigate chemical reactions, using instruments, tools, and apparatus safely, accurately, and effectively (e.g., evaporating water in a neutralization reaction to recover the salt; determining the properties of acids and bases; simple synthesis, decomposition and oxidation reactions);
CH2.01F – communicate scientific ideas, procedures, results, and conclusions about chemical reactions using appropriate language and formats (e.g., sharing in small groups; demonstrations; structures laboratory reports).
Task 2.12 requires the preparation of a research paper on suggested topics involving acids and bases. Preplan with teacher/librarian and book access to computer lab or Internet.
Equipment required for Task:
· 2.1 – Video on “Acids and Bases”, or antacid ads from magazines. Teachers are reminded to follow copyright regulations when showing videos.
· 2.2 – apple, lemon, brussel sprouts, dill pickles, milk, tonic water, vinegar
· 2.3 – dilute (less than 0.01M) acetic acid, dilute (less than 0.01M) hydrochloric acid, blue and red litmus paper, phenolphthalein indicator, tap water, magnesium ribbon, dilute (less than 0.01M) sodium hydroxide solution, dilute (less than 0.01M)
· dilute (less than 0.01M) ammonium hydroxide solution, test tubes, slides, glass stirring rods
· 2.4 – zinc metal, dilute (less than 0.01M) hydrochloric acid
· 2.5 – molecular model kits
· 2.7 – antacid tablets, toilet bowl cleaner, lemon juice, coffee, vinegar, liquid stomach antacid, drain cleaner, window cleaner, bleach, tea, and the following indicators (methyl orange, phenolphthalein, litmus, bromothymol blue), pH paper (Universal indicator)
· 2.8 – universal indicator paper, orange, grapefruit, milk, vinegar, aspirin, grape juice (white), calcium hydroxide solution, ammonium hydroxide solution, potassium hydroxide solution, water, ground almond solution, glass cleaner
· 2.9 – sodium hydroxide solution, tap water, hydrochloric acid solution, silver nitrate solution, indicator, pH paper (Universal indicator), evaporating dish, graduated cylinder, medicine dropper, glass stirring rod
· 2.10 – neutralized solution from Task 2.9, retort stand, noculating loop, wire gauze, Bunsen burner, evaporating dish, glass slide, microscope, medicine dropper, silver nitrate solution
The understanding of and ability to practise safety in the laboratory developed in the previous activity is revisited.
Students view a video on acids/bases (Bill Nye) or look at an ad on acids and bases (Antacids) and participate in a teacher led discussion on acids and bases, found in both home and workplace products, and their use.
Teacher Facilitation
1. Utilize a video resource on acids/bases to introduce this activity. Teachers are reminded to follow all copyright regulations when showing videos. Alternately, look at advertisements in magazines on antacids. [Note: The key ideas for this unit are: acids and bases have numerous uses in everyday life; compounds classified as acids have characteristic properties; compounds classified as bases have characteristic properties, some of which are different from those of acids; chemical and natural indicators undergo a colour change in the presence of acids and bases; neutralizations are important acid-base reactions; acids and bases can be corrosive and must be handled with extreme caution. Many acids and bases are not corrosive. For example, cola drinks have acidic properties and they are consumed. Antacids, both solid and liquid, are consumed to aid in treating heartburn symptoms; and acids and bases can be recognized by their names.]
2. Carry out a teacher-led discussion that elaborates on the key ideas of this unit.
3. Have students record the key ideas in a short note.
Assessment
None.
Accommodations
Use scribe, and/or peer helper, tape recorder, or computer as an alternative to written response.
Students classify different foods according to taste in chart form. If students have food allergies, substitutions can be made.
Teacher Facilitation
1. Obtain a variety of foods for use in this lab including apple, milk, lemon, tonic water, brussel sprouts, vinegar, and dill pickles.
2. Remind the students that tasting substances is rarely carried out in a lab.
3. Provide a lab worksheet for recording data. See Appendix 2.16.
4. The worksheet has a question involving the types of acids associated with foods. The following information may prove to be useful:
|
Substance |
Name of Acid |
|
orange, lemon, grapefruit |
citric |
|
sour milk, sour cream |
lactic |
|
vinegar |
acetic |
|
aspirin |
acetylsalicylic |
|
apple, grape |
malic |
Safety Precautions
Teacher should check with all students regarding food allergies. Preparation of the food for tasting should involve careful procedures. Teacher prepares food and stores it in a sealed container or covers it with plastic wrap. All students should wash their hands at the beginning of the lab to maintain aseptic conditions. Liquids should be poured from a sealed container into paper cups that can be disposed of after taste testing has been carried out. Students should be instructed not to share food that has been tasted by themselves with others. Food is disposed after being tasted by the student.
Assessment
Assess using a worksheet answer key.
Accommodations
Data can be recorded with peer assistance. Enlarged print can be utilized for sight-impaired students.
Students use litmus paper to identify common acids and bases. This data is recorded in chart form. The effect of acids and bases on magnesium ribbon and phenolphthalein indicator will also be recorded. A simple touch test will also be performed with acids and bases.
Teacher Facilitation
1. Lead discussion on how using taste for identifying acids and bases is not only impractical, but extremely dangerous.
2. Introduce the concept of using an indicator in the form of litmus paper for identifying acids and bases. Litmus is a dye that is extracted from a type of plant called lichen. Litmus is blue in its natural state and turns red if an acid is added to it. Red litmus turns blue if a base is added to it. Tea can also be used as an indicator; it forms a red solution in an acid and dark brown solution in a base.
3. Students observe and record the effect acids and bases have on blue and red litmus paper, phenolphthalein indicator, magnesium ribbon, and on human skin (simple touch test) in chart form on worksheet provided. (See Appendix 2.17.)
4. The touch test will only be carried out on the dilute vinegar and the dilute (less than 0.01M) sodium hydroxide solution.
5. Note: Teacher may substitute indicator paper with a pH meter if one is available. The use of a pH meter could also serve as an extension to this task.
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Disposal: Refer to federal, provincial, and local guidelines.
The following MSDS information is provided:
Acetic acid (vinegar): Do not use glacial acetic acid for this experiment. Use household vinegar. Flush down drain with excess water.
Ammonium hydroxide: Use microamounts when using. Danger! Corrosive. Toxic. Dispose of in waste disposal jar.
Hydrochloric acid: Add acid to water and not water to acid when carrying out a dilution. Use microamounts when using. Corrosive! Absorb spills using an absorbent, non-combustible material such as earth, sand, or vermiculite. Dispose of using a waste disposal jar.
Magnesium: Use microamounts when using. Dispose of using a waste disposal jar.
Phenolphthalein: Use microamounts when using. Dispose of using a waste disposal jar.
Sodium hydroxide: Danger! Corrosive. Causes severe eye and skin burns. Contact with moisture or water may generate sufficient heat to ignite nearby combustible materials. Ensure that the dilution of sodium hydroxide in this lab is 0.001 M. Wash thoroughly with water after any contact is made. Dispose in a waste disposal jar.
Assessment
Assess using worksheet answer key.
Accommodation
Pair students to complete experiment. Have a scribe aid in completion of worksheet.
Students participate in a teacher-led discussion that elaborates on the characteristics of acids and bases. The labs carried out in Task 2.2 (Sour vs. Bitter) and 2.3 (Properties of Acids and Bases) provide the knowledge/fact base for this note.
Teacher Facilitation
1. Carry out a demonstration involving zinc metal and hydrochloric acid to introduce this activity. The production of hydrogen gas can be demonstrated by carrying out a burning splint test. This demonstration begins the discussion of acids and bases.
2. Remind the students of the two labs that were carried out in prior classes (Sour vs. Bitter and Properties of Acids and Bases)
3. Note: Acids are a group of substances that have the following properties: acids conduct electricity when in solution, acids react with active metals to liberate hydrogen gas, acids change the colour of litmus and other dyes (turns blue litmus red), acids react with bases to form new substances, acids react with carbonates and bicarbonates, and acids have a sour taste.
4. Note: Bases are a group of substances that have the following properties: bases conduct electricity when in solution, bases change the colour of litmus and other dyes to colours different from those of acid solutions (turns red litmus blue), bases react with an acid to produce new substances, bases are slippery to the touch, bases do not react with carbonates and bicarbonates, and bases have a bitter taste.
Assessment
None.
Accommodations
Provide a peer helper to assist students with writing when necessary.
Students are given the definition of a chemical formula (series of symbols of elements linked together to form the symbolic representation of a compound; it shows the relative number of atoms of each element in the compound) and apply this definition to a worksheet involving common acids and bases. The elements present and their relative number are identified in chart form with the use of a periodic table.
Teacher Facilitation
1. Prepare a note that covers the basics behind a chemical formula. A chemical formula represents a series of elements that are linked together to form a compound.
2. Utilize a molecular model kit to demonstrate common acids and bases that have been used in the lab: HCl (Hydrochloric acid), H2SO4 (Sulfuric Acid), NaOH (Sodium Hydroxide).
3. Indicate to the students how the Periodic Table is used to identify the element and how the subscript number that follows the symbol of the element in a formula identifies the total number of atoms of each element in the acid or base compound.
4. Provide a chart as follows: (See also Appendix 2.18)
|
Formula |
Elements
Present |
Number
of Each Element |
Acid/Base |
Name |
|
HC1 |
Hydrogen Chlorine |
1 1 |
Acid |
Hydrochloric Acid |
|
HNO3 |
|
|
|
Nitric Acid |
|
NaOH |
|
|
|
|
Assessment
Worksheet answer key
Accommodations
Provide a peer helper to assist students with writing when necessary.
Students read a pH scale and identify on this scale where common acids and bases are found. The strength of acids and bases is measured by using the pH scale.
Teacher Facilitation
1. Lead a discussion on scales and how they are used in all walks of life. Describe a scale as the rule or system upon which a series is laid down. Provide common examples of scales that are used everyday, e.g., measuring temperature with a thermometer, measuring speed with a speedometer, measuring volume with a graduated cylinder, mass measurement with a balance, and length measurements with a ruler.
2. Introduce the pH scale as a scale that is used to measure the strength of acids and bases. (Note for teacher reference: the pH scale is logarithmic; for every decrease of 1 in the pH scale, the acid strength increases by 10X; therefore, an acid with pH of 2 is 10X more acidic that an acid with pH 3).
3. Provide students with universal pH paper and the colour coded scale so as to show that the pH scale is a numerical scale that runs from 0 to 14.
4. Provide students with a pH table that indicates where some common substances exist. See Appendix 2.19.
5. Students use Appendix 2.19 to indicate on a pH scale where some common substances exist. Students interpret the table of pH values and use a ruler to graphically indicate where these substances are found on the pH scale.
6. As enrichment, students could test the substances used in step 5 using a pH meter and compare the pH values obtained using the meter and with those using the universal pH paper.
Assessment
Create an answer sheet for Appendix 2.19.
Accommodations
Provide a scribe for recording answers.
Students test ten common household products for their acidic or basic characteristics and record their observations in chart form. Acidic and basic properties are determined through the use of chemical indicators (e.g., methyl orange, phenolphthalein, litmus, and bromothymol blue).
Teacher Facilitation
1. Lead a discussion on indicators and how they are used to determine the characteristics of a substance. Acidic and basic substances can be identified using chemical indicators. The following chart is provided:
|
Indicator |
Colour In Acid |
Colour In Base |
|
Methyl orange |
Red |
Yellow |
|
Litmus |
Red |
Blue |
|
Bromothymol blue |
Yellow |
Blue |
|
Phenolphthalein |
Colourless |
Pink |
2. Introduce the fact that many common household products contain either acids or bases. Each product has its own chemical properties that make it useful for different chores. When you have a tough cut of beef, you can make it tender by marinating it. The marinade, whether it is lemon juice, wine, or vinegar reacts with the tough connective tissue to soften it. These are liquids that have acidic properties. Soaps, which are used to clean dishes, clothes, and hands, contains a base that reacts with the oils and dirt to remove them.
3. Introduce Appendix 2.20. Students test for acids and bases in ten consumer products using the indicators introduced at the beginning of this discussion.
4. Review lab routines and safety procedures with the students. The Lab Safety Checklist (Appendix 2.2) and Lab Procedures Rubric (Appendix 2.3) could be introduced to the students as the assessment tools that will be used to monitor lab safety.
5. Demonstrate how to use pH paper (Universal) to determine if a solution is acidic, basic, or neutral.
6. Introduce the concept of acidic, basic and neutral solutions by discussing some characteristics such as taste, e.g., acids such as vinegar, and lemon juice taste sour; bases, such as liquid antacids, solid antacids, and almond oil, taste bitter; colour of indicator (Universal) reflects the pH level; and the effects on living organisms (e.g., both strong acids and strong bases are corrosive).
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Disposal: Refer to federal, provincial, and local guidelines.
Caution: Strong acids and bases are corrosive.
Use microamounts of the consumer products tested. Dispose of using a waste disposal jar.
The following MSDS information is provided:
Bromothymol blue: Use microamounts. Regarded as an essentially non-hazardous chemical that may stain skin. Dispose of by flushing down the drain with excess water.
Phenolphthalein: Use microamounts. Dispose of using a waste disposal jar.
Methyl orange: Use microamounts. Dispose of using a waste disposal jar.
Litmus: Use microamounts. Dispose of using a waste disposal jar.
Assessment
Assess student work using a teacher created answer key. Assess lab work using Lab Procedures Rubric (Appendix 2.3) and Lab Safety Checklist (Appendix 2.2).
Accommodations
Teachers may choose to have students complete only part of this activity. A scribe may be assigned for students who might have difficulty completing the lab and accompanying worksheet.
Students determine the pH of 12 household products using universal indicator paper. This information is recorded in chart form and the substances are determined to be acidic, neutral, or basic.
Teacher Facilitation
Prior to lab:
1. Prepare the following samples for the pH lab including: orange, grapefruit, milk, vinegar, aspirin, grape juice (white), calcium hydroxide solution (less than 0.01M), ammonium hydroxide solution (less than 0.01M), potassium hydroxide solution (less than 0.01M), water, ground almond solution, and glass cleaner.
2. Prepare a worksheet to guide students in performing the lab and entering their data. (See Appendix 2.21).
3. Obtain a supply of universal indicator paper that is colour coded for recording the pH level of the substances used in this lab activity.
During lab:
4. Students follow the Lab Procedures Rubric (Appendix 2.3) and the Lab Safety Checklist (2.2) during this lab activity. Introduce these tools at the beginning of the lab activity.
5. Demonstrate how to use the universal indicator paper and how to determine the pH value from the colour code provided.
6. Record the information from this lab in the worksheet provided (Appendix 2.21).
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Disposal: Refer to federal, provincial, and local guidelines.
Use microamounts of household and commercial products when testing for pH.
The following MSDS information is provided:
Ammonia water: Use microamounts. Dispose of using a waste disposal jar.
Calcium hydroxide: Use microamounts. Caustic irritant to eyes, skin, and respiratory tract. Dispose of using a waste disposal jar.
Potassium hydroxide: Use microamounts. Caustic irritant to eyes, skin, and respiratory tract. Dispose of using a waste disposal jar.
Assessment
Assess lab work using Lab Procedures Rubric (Appendix 2.3) and Lab Safety Checklist (Appendix 2.2). Assess student work using teacher-created answer key.
Accommodations
Provide a scribe to assist in recording data. Lab partners can be arranged to assist in aiding students throughout this lab activity.
Students carry out and observe a neutralization reaction. A base will be neutralized by the addition of an acid and the amount of acid that is required to neutralize the base is recorded. The neutralization reaction is observed using an indicator.
Teacher Facilitation
1. Introduce the concept of neutralization by referring to the pH scale. The middle point of the pH scale (7.0) represents the point at which the substance is neither acidic or basic. Distilled water can be used to demonstrate neutrality with the use of a universal indicator strip, and/or a liquid indicator that has been used in past experiments (methyl orange, litmus, phenolphthalein, or bromothymol blue). (Note: Distilled water is mildly acidic because it contains dissolved CO2; let it sit overnight before using the distilled water. Depending on the geographical location, tap water may be slightly acidic or basic).
2. Provide the students with the lab worksheet (Appendix 2.22). Go over the lab worksheet and the requirements for this lab activity.
3. Students should be informed that they will be observing and recording a neutralization reaction in the lab.
4. Students use universal indicator paper, dilute (less than 0.01M) hydrochloric acid, and dilute (less than 0.01M) sodium hydroxide solution in this lab. The pH of the original solutions is recorded, and the pH of the final solution after it has been neutralized is recorded as well. Phenolphthalein is used as the indicator for this experiment.
5. Save the material in the evaporating dish as it will be used for the next Task (2.10: What is a Salt?).
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Disposal: Refer to federal, provincial, and local guidelines.
Use microamounts of materials if possible.
The following MSDS information is provided:
Hydrochloric acid (dilute - less than 0.01M): Add acid to water and not water to acid when carrying out a dilution. Absorb spill using an absorbent, non-combustible material such as earth, sand, or vermiculite.
Phenolphthalein: Use microamounts. Dispose of using a waste disposal jar.
Sodium hydroxide: Danger! Corrosive. Causes severe eye and skin burns. Contact with moisture or water may generate sufficient heat to ignite nearby combustible materials. Use microamounts. Dispose of using a waste disposal jar.
Assessment
Use Lab Safety Checklist (Appendix 2.2) and Lab Procedures Rubric (Appendix 2.3) to assess lab work. Assess student work using teacher-created answer key.
Accommodations
Group students so that they can assist one another.
Student utilizes the neutralized material (hydrochloric acid and sodium hydroxide) from Task 2.9 to observe and record the products of a neutralization reaction.
Teacher Facilitation
1. Lead a brief discussion on the results of the last lab activity (Task 2.9). Discuss that when an acid is mixed with a base, the new solution is neither an acid nor a base. It is neutral. The process is called neutralization. The pH of a neutralized solution is 7.0.
2. Provide the chemical formula for the substances involved in the reaction from Task 2.9.
|
Substance |
Chemical Formula |
Elements Present |
|
Sodium hydroxide |
NaOH |
Na, O, H |
|
Hydrochloric acid |
HCl |
H, Cl |
3. Have students hypothesize the possible products of this reaction. Record the results on the board for reference after the lab activity is carried out.
4. Provide the students with a lab activity sheet involving salts (Appendix 2.23). Go over the steps of this lab activity. The focus of this lab activity is to observe and record the products from a neutralization reaction.
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Disposal: Refer to federal, provincial, and local guidelines.
The following MSDS information is provided:
Hydrochloric acid: Caution! Caustic. Use microamounts. Dispose of using a waste disposal jar.
Sodium hydroxide: Danger! Corrosive. Causes severe eye and skin burns. Contact with moisture or water may generate sufficient heat to ignite nearby combustible materials. Dispose of using a waste disposal jar.
Assessment
Use Lab Safety Checklist (Appendix 2.2) and Lab Procedures Rubric (Appendix 2.3) to assess lab work. Assess student work using teacher-created answer key.
Accommodations
Pair students of appropriate ability level together to assist in recording of observations and reading comprehension.
Students complete a Reading for Understanding assignment on Acid Rain, its sources, its effects, and how it can be stopped.
Teacher Facilitation
1. Students participate in a teacher-led discussion on acid rain, what it is, where it originates from, and how this environmental problem can be addressed. Points brought up throughout the discussion can be placed on the board.
2. A Reading for Understanding assignment on Acid Rain (Appendix 2.24) is handed out and students complete the assignment questions and the accompanying Cloze worksheet assignment.
Assessment
Assess using Reading for Understanding Rubric (Appendix 2.14).
Accommodations
Provide a peer helper/scribe to assist in reading and recording answers.
Note: Teachers may choose to use this task as a summative assessment in which case each student is graded individually. Students participate in a teacher-led discussion on acid rain, its effects, and how it can be reduced. Based on discussion, class generates a list of topics that are connected to acid rain and the environment. Students complete a research paper using the Research Paper Template. (See Appendix 2.31).
Teacher Facilitation
1. The focus of this activity is to emphasize the danger of acid rain to the environment.
2. Lead students through a discussion on the effects of acid rain and the resulting harmful effects on the world in which we live. Use pictures and/or video clips to aid in the discussion if desired. Teachers are reminded to follow copyright regulations when showing videos
3. Aid students in organizing the list and recording it in their notebooks.
4. Instruct students to choose one of these factors and complete a research paper. Students should use the Research Paper Template (Appendix 2.31) focussing on the problem and any solutions.
5. Some possible topics for this research paper assignment are as follows: where acid rain comes from; effect of acid rain on aquatic organisms; effect of acid rain on plant life; effect of acid rain on terrestrial organisms; treatment of acidified lakes; treatment of acidified soil; effect of acid rain on marble buildings and tombstones; production of acid rain, regional study of acid rain fallout; why limestone lakes of Eastern Ontario are not affected by acid rain; and the effect of acid rain on human health.
6. Provide students with research material and access to the library and the Internet.
Assessment
Assess using the Research Paper Rubric (Appendix 2.33).
Accommodations
Assign a peer helper to assist with research and reading. Use scribe, tape recorder, or computers as an alternative to written responses.
See resources for the unit, particularly those dealing with acid rain.
Time: 420 minutes
Chemical reactions in everyday life are examined with the specific focus on the use of common chemical reactions in various careers. Students complete a culminating activity that examines the impact of chemistry (more specifically chemical reactions) on the environment.
Strand(s): Chemistry
Overall Expectations
CHV.03 – demonstrate an understanding of the differences between chemical and physical changes.
Specific Expectations
CH2.01B – formulate scientific questions about chemical reactions (e.g., how does changing the temperature affect the rate of the reaction?);
CH2.01D – select information from various sources to answer the questions formulated;
CH2.01E – organize, record, and analyse the information gathered during investigations of chemical reactions (e.g., charts, tables, graphs);
CH3.01 – identify the uses of acids, bases and salts in the workplace or home environment by researching labels on common household products;
CH3.02 – describe activities in the workplace and household where knowledge of chemicals can prevent hazardous situations;
CH3.03 – identify careers or hobbies where a knowledge of chemical reactions is important.
Task 3.5 – arrange a guest speaker to discuss a career related to chemistry
Task 3.6, 3.7, and 3.8 – pre-plan visit with teacher/librarian or book computer lab time for research using the Internet
Equipment required for Task:
· 3.1 – lab equipment to be determined by teacher
· 3.2 – samples of comic strips, material for comic strip (pencil crayons, paper)
· 3.3 – enlarged labels of three household products
· 3.4 – ten common household products, representative of acids, bases, and salts
· 3.6 – research material (newspapers, videos, CD-ROMs)
· 3.7 – poster making materials (crayons, markers, bristle board)
· 3.8 – video on current environmental chemistry issue
Teachers are reminded to follow copyright regulations
Several expectations from Grade 9 are revisited. Knowledge of chemical reactions and physical/chemical change are developed further. Safety and WHMIS are examined with focus on their applications in everyday life.
Students participate in small lab activities involving chemical reactions in everyday life. The lab activity is used as a basis for a class discussion and concept mapping activity.
Teacher Facilitation
1. Gather materials to carry out a variety of lab activities including bleaching cloth, tye-dyeing T-shirts, fermentation of yeast, or cooking food. (See Appendix 2.25). Materials gathered may also include pictures of various chemical reactions including a running car, a person smoking a cigarette, a fire burning, etc.
2. Lead a discussion focussing on how chemistry applies to everyday life.
3. Complete concept mapping activity (Appendix 2.9) which focusses on everyday chemical reactions. Possible descriptors include: chemical reactions, cleaning, combustion, cooking, baking, etc. Connectors include: at work, at home, such as, including.
Safety Precautions
Students are to wear goggles and protective clothing; hands should be washed thoroughly after the lab. Waste should be disposed in a waste disposal jar.
Assessment
None.
Accommodations
Pair students for lab work. Some experiments can be done as teacher demonstrations.
Students create a comic strip showing four chemical reactions in their everyday lives.
Teacher Facilitation
1. Review the idea of chemical reactions in everyday life.
2. Gather examples of various comic strips for students to examine. Direct students to locate examples of chemical reactions in comic strips. Students circle each example and write a sentence describing the chemical reaction.
3. Post comic strips around the room for future reference.
4. Create a worksheet to lead students through the activity of creating a comic strip showing four chemical reactions in everyday life.
5. Discuss Comic Strip Checklist (Appendix 2.26) so students are aware of the evaluation to be used.
Assessment
Assess using Comic Strip Checklist (Appendix 2.26).
Accommodations
Allow students to present information in a form other than a comic strip (e.g., poster, video, rap song, slide presentation, or drama).
Students identify ingredients on common household products as acids, bases, or salts. Students summarize findings on a worksheet.
Teacher Facilitation
1. Enlarge labels found on three common household products.
2. Lead students though activity in which students identify product; the active ingredient in product that is an acid, base, or salt; and the use of the product. See Appendix 2.27 for sample worksheet.
3. Examples of products include a cola which contains phosphoric acid and carbonic acids. In soya sauce and bouillon cubes there is sodium chloride (salt); drain cleaner contains sodium hydroxide (base); yogurt contains lactic acid.
Assessment
Assess using teacher-created answer key.
Accommodations
Assign a peer helper to assist with writing.
Students complete worksheet identifying ten common household products as acids, bases, or salts.
Teacher Facilitation
1. Gather ten household products containing acids, bases or salts.
2. Prepare worksheet to guide students through the activity. (See Appendix 2.28)
3. Examples of products include: vinegar which contains acetic acid, citrus fruits (acidic), most cleaning products (e.g., laundry detergent, floor cleaner) contain bases and salts.
Assessment
Assess using teacher-created answer key.
Accommodations
Assign a peer helper to assist with reading and writing.
Student awareness of chemical reactions in everyday life is broadened with a visit from a guest speaker. Students learn about chemical reactions that are used everyday on the job.
Teacher Facilitation
1. Arrange a guest speaker to talk to the class about his/her job. Discussion should also cover the chemicals used, with emphasis on the safety precautions used on the job. Possibilities include the school custodian, a cosmetologist, a technician from a paint manufacturer, and a salesperson from a cleaning products supplier.
Assessment
None.
Accommodations
Use of video or teacher-developed Reading for Understanding article if guest speaker is unavailable.
Students research careers in which knowledge of chemistry and chemical reactions is essential. Information is recorded on a worksheet for use in poster making activity.
Teacher Facilitation
1. Lead a brainstorming activity on careers which use chemical reactions. Instruct students to choose one career from list generated.
2. Create a worksheet to guide students through the activity. Focus student research on careers and the chemistry involved in the job. (See Appendix 2.29) Worksheet should also have a section created in which students record information about safety precautions used in the career being researched. This information will be used in the next task.
3. Provide students with information on careers listed. Information could come from newspapers, the Internet, library searches, CD-ROMs.
Assessment
Assess using teacher-created checklist.
Accommodations
Provide peer helpers to assist with research and writing.
Using research from Task 3.6, students create a safety poster. The poster shows the chosen career with emphasis on the safety precautions that are taken on that job.
Teacher Facilitation
1. Gather poster-making materials.
2. Introduce students to Poster and Presentation Rubric (Appendix 2.30) so they become familiar with criteria of evaluation and are able to judge the quality of the poster they are creating.
3. Assist students in organization of material and time management.
Assessment
Assess using poster portion of Poster and Presentation Rubric (Appendix 2.30).
Accommodations
Allow students to present information in a form other than a poster (e.g., a video, slide presentation, drama, comic strip, or any other suitable form of communication). Teachers are reminded to follow copyright regulations when showing videos.
Students view video or short TV segment on chemistry in the environment and complete a question sheet.
Teacher Facilitation
1. Select and show a video that focuses on environmental chemistry (e.g., cigarette smoking, acid rain, global warming, the banning of pesticides/herbicides in communities, the safe disposal of oil, the clean up of oil spills, the effects of cigarettes smoking on the body, the disposal of chemicals in the home, the effect of using solvents, such as turpentine, when cleaning skin). Teachers are reminded to follow copyright regulations when showing videos.
2. Prepare a worksheet with focus questions on video. Sample questions may include: “What is the problem?, “What are the causes of the problem?”, “What effect does the problem have on the environment?”.
3. Lead a discussion on the environment and the effects of chemical reactions.
4. Alternate assignment: Students select a news article with the same focus. Students then answer the five W and H questions (who, what, where, when, why and how).
Assessment
Assess using teacher-created answer key.
Accommodations
Use of closed-captioning for deaf and hard of hearing students. Assign a peer helper to assist in the completion of the worksheet.
Students complete an SLL entry on a current environmental issue.
Teacher Facilitation
1. Prepare an SLL entry sheet with vocabulary (e.g., chemistry, reaction, pollution, pesticide) and focus task (e.g., “I think pesticides should or should not be banned because…”). Include a connections statement (e.g., “One thing I would like to learn about how chemistry affects the environment is…).
Assessment
Assess using SLL Rubric (Appendix OV-3).
Accommodations
Provide peer helper to assist with writing.
Note: Teachers may choose to use this task as a summative assessment in which each student would be graded individually. Using connections question generated from SLL entry in Task 3.9, students complete a research paper examining the influence chemistry has on the environment. Students are to formulate a question and use it as the basis for their research. Students complete a Research Paper Template (Appendix 2.31) on the environmental issue.
Teacher Facilitation
1. Go through model Research Paper Template Sample with students explaining how it follows the template (Appendix 2.32).
2. Students using connections question from SLL entry in previous task as basis for research paper.
3. Prepare materials and book access to Library/Resource Centre and Internet.
4. Introduce students to assessment tool and format of research paper.
Assessment
Assess using Research Paper Rubric (Appendix 2.33).
Accommodations
Assign a peer helper to assist with reading and research. Use scribe, tape recorder, or computer as an alternative to written responses.
Environment Canada’s web site with a
primer on ozone depletion
http://www.ec.gc.ca/ozone/primer/index.htm
Reference for Unit 2, Task 1.1.
Parts and Functions
Complete the following chart by matching the correct name with the use of the item. Sketch a picture to represent the item. Sample answers are given for 3 and 11.
|
Item |
Name (from list) |
Description or Sketch |
Uses or Function (from list) |
|
1 |
|
|
|
|
2 |
|
|
|
|
3 |
fire Extinguisher |
red cylinder (sketch of fire extinguisher with cone nozzle and handle) |
E.Puts out fires |
~
|
10 |
|
|
|
|
11 |
test tube |
(sketch of test tube) |
J. Glass tube, rounded on bottom, that holds about 30 mL of liquid |
|
12 |
|
|
|
|
Item Names |
|
Use or Function |
|
first-aid kit |
A. |
Broken glassware goes into it |
|
Safety goggles |
B. |
Measures temperature in Celsius degrees |
|
fire extinguisher |
C. |
Produces a gas flame for heating |
|
250 mL beaker |
D. |
Used to measure up to 100 mL of liquid |
|
hot plate |
E. |
Puts out fires |
|
microscope |
F. |
Protects eyes when working in a lab |
|
100 mL graduated cylinder |
G. |
Electrical devices used to heat materials |
|
broken glass container |
H. |
Magnifies biological specimens so you can see them |
|
thermometer |
I. |
Used to wash splashed material from the eye |
|
eye wash station test tube |
J. |
Glass tube, rounded on bottom that holds about 30 mL of liquid |
|
Erlenmeyer flask waste blanket |
K. |
Made of glass, liquids are mixed in it, holds about 200 mL |
|
fire blanket |
L. |
Flask with conical shape |
Reference for Unit 2, Task 1.2, 1.5, 1.8, 2.7, 2.8, 2.9. 2.10
Date: Name:
Check if the item is done correctly.
|
Able to explain use of - eyewash station |
q |
|
- fire extinguisher |
q |
|
- fire blanket |
q |
|
|
|
|
Wears goggles throughout experiment |
q |
|
|
|
|
Has long hair tied back/no loose clothing |
q |
|
|
|
|
Disposes of broken glass, biology specimens or chemical waste in proper location |
q |
|
|
|
|
Operates equipment safely |
q |
|
|
|
|
Follows special instructions |
q |
|
|
|
|
Takes correct amount of reagent/solution |
q |
|
|
|
|
Does not return reagent nor contaminate source |
q |
|
|
|
|
Informs teacher of accident/injury |
q |
|
|
|
|
Behaves safely |
q |
|
|
|
|
Knows location of fire exit |
q |
|
|
|
|
Checks all electrical circuits, frayed cords with teacher |
q |
|
|
|
|
Identifies potential hazards in labs |
q |
Reference for Unit 2, Task 1.2, 1.5, 1.8, 2.7, 2.8, 2.9, 2.10
These criteria measure good performance in the laboratory
|
Criteria |
Level 1 |
Level 2 |
Level 3 |
Level 4 |
|
Follows procedures |
- participates in lab with supervision - written instructions need oral interpretation |
- participates in lab with some supervision - all oral instructions followed/some written instructions followed |
- participates in lab with minimal or no supervision - can follow written instructions |
- actively assists others in completing lab - able to read written instructions and assists others in interpreting them |
|
Application of technical skills and procedures |
- applies technical skills and procedures with limited competence |
- applies technical skills and procedures with moderate competence |
- applies technical skills and procedures with considerable competence |
- applies technical skills and procedures with a high degree of competence |
|
Use of tools, equipment, and materials |
- uses tools, equipment and materials correctly with supervision |
- uses tools, equipment and materials correctly with some supervision |
- uses tools, equipment and materials correctly |
- demonstrates and promotes the correct use of tools, equipment and materials |
|
Concentration |
- wanders away from lab area and disturbs others - voice often sufficiently loud to disturb others |
- mostly works conscientiously at own station, travel to pick up materials is not always direct - voice is usually sufficiently quiet to not disturb others |
- works on task, travel is purposeful and only to pick up equipment or ask the teachers questions - use of voice is usually appropriate |
- always on task, assists others to stay on task, recognizes when teacher needs to direct whole class, travel is organized and non-disturbing - questions deal with lab and voice is quiet. |
|
Cleanup |
- needs reminders to cleanup, sometimes misplaces equipment |
- usually cleans up sink, equipment, and lab bench |
- always cleans up and returns equipment, discards material in proper place, cleans sink and lab bench |
- thorough cleanup and monitors others, assist in collecting and distribution of materials |
|
Safety |
- uses tools, equipment, and materials safely only with supervision and prompting |
- uses tools, equipment, and materials safely with some supervision and occasional prompting |
- always uses tools, equipment, and materials safely |
- demonstrates, promotes, and monitors the safe use of tools, equipment, and materials at all times |
|
Disposal of excess/used substances |
- needs prompting to carry out disposal in a safe manner - needs to be directed to correct location, and to follow disposal instructions |
- seldom needs prompting - usually done in a safe manner, to correct location, to where instructed |
- no monitoring or prompting necessary - always done in a safe manner, to correct container, to where instructed |
- assists in monitoring others - always in a safe manner, to proper location with obvious thought on why, where instructed |
(Adapted from The Ontario Curriculum, Science, Grades 9 and 10, (1999) page 46 – 47.)
* These categories are for diagnostic purposes only. They may be used to provide students with feedback during lab activities.
Reference for Unit 2, Task 1.2
Name:
Date:
Fizzy Pop Lab
Introduction: The purpose of this lab activity is to introduce the class to proper lab procedures, safe handling of glassware and chemicals, and the proper way of recording observations. This experiment will also answer the question, “What makes the ‘fizz’ sound in a soft drink?”.
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing lab.
Disposal: Use the waste disposal jar for the mothballs.
Aim: To determine what makes the ‘fizz’ sound in a soft
drink.
Apparatus
400 mL beakers (2)
2 mothballs
water
diluted vinegar (300 mL water plus 50 mL vinegar)
10 mL baking soda solution (10 g baking soda in 200 mL water)
safety glasses
Method
1. Pour 350 mL of water into a 400 mL beaker.
2. Drop 1 mothball into the water. Record the observations in the chart provided.
3. Prepare the diluted vinegar in the second 400 mL beaker. Add a mothball to that beaker. Record the observations in the chart provided.
4. Add 5 mL of baking soda solution to each container. Record your observations for each beaker. What do you observe for each liquid?
5. Describe the motion of the mothball in the fizzy liquid in chart form.
6. Carefully observe the surface of the mothballs. What forms on the surface of the mothballs?
7. What happens to the mothball once it rises to the surface of the beaker? Where do the bubbles go?
8. Clean up your work area.
Observations
|
Lab Step |
Observations |
|
Mothball in water |
|
|
Mothball in diluted vinegar |
|
|
Mothball in water/baking soda solution |
|
|
Mothball in diluted vinegar/baking soda solution |
|
|
Motion of mothball |
|
|
Surface of mothball |
|
Conclusions
Instructions: Answer the following questions in sentence form. Refer to your observations.
1. What is produced by adding baking soda to vinegar?
2. What causes the fizz in a liquid?
3. What causes the mothball to rise in one of the beakers and not in the other?
4. What happens when a mothball reaches the surface?
5. Why does the mothball sink after reaching the surface of the fizzy liquid?
6. Does anything unusual happen to the plain water, a non-fizzy liquid?
7. What is unusual about the behaviour of mothballs in a fizzy liquid? What causes this behaviour?
8. Why were safety glasses worn in this experiment?
Reference for Unit 2, Task 1.3
Physical vs. Chemical Change Assignment
Name:
Date:
Instructions: Knowing the difference between a physical and a chemical change is crucial when working with chemicals in the home and in the workplace. Use the following checklist for Physical and Chemical Change characteristics to categorize the pictures provided as either Physical or Chemical. Record, in the checklist outlined on this sheet, the category that the picture belongs to and the reason why it has been placed in the physical or the chemical change column.
|
Physical Change Characteristics · A physical change alters only the form of a substance. · Physical changes are reversible. · The chemical compositions of substances are not changed in physical changes. |
|
Chemical Change Characteristics · A chemical change transforms a substance into a new product. · Chemical changes are not reversible. (Teacher Note: in a closed system, chemical reactions are often reversible; in many lab conditions where the system is open or when a gas or precipitate are formed, chemical reactions are not readily reversible). · Any, or all of the following, are characteristics of chemical change: production of heat, light, gas, precipitate; colour change. |
|
Picture Number |
Physical Change |
Chemical Change |
Reason Why It Is a Physical or a Chemical Change that is
Represented in Picture |
|
1 |
|
|
|
|
2 |
|
|
|
|
3 |
|
|
|
|
4 |
|
|
|
|
5 |
|
|
|
Conclusions
1. What pictures demonstrated physical changes occurring?
2. What pictures demonstrated chemical changes occurring?
3. List two examples of chemical changes and two examples of physical changes that are not in this assignment.
Reference for Unit 2, Task 1.4
Physical vs. Chemical Change Checklist
Name:
Background: In a physical change no new substances are formed. An example of a physical change would be water turning into ice. The change is reversible. In a chemical change a new substance is formed. When wood is burned the following products are created: heat, light, gas, and carbon ash. Chemical changes are characterized by the following things: heat absorbed/released, light produced, gas produced, colour change, and precipitate forming.
Assignment: Indicate in the following chart whether the change indicated is either a physical or a chemical change. Use your notes and past assignments to provide the reason for the classification made.
Write PHYSICAL or CHEMICAL next to each change. Give a brief reason for your answer.
|
Change |
Physical or Chemical Change? |
Reason |
|
1. burning wood |
|
|
|
2. breaking glass |
|
|
|
3. water evaporating |
|
|
|
4. car battery powers car |
|
|
|
5. the wind blowing |
|
|
|
6. sugar being burned |
|
|
|
7. making ice cubes |
|
|
|
8. grinding steel |
|
|
|
9. dry cleaning clothes |
|
|
|
10. drying clothes |
|
|
|
11. volcano erupting |
|
|
|
12. paint drying |
|
|
|
13. bread making |
|
|
|
14. boiling a potato |
|
|
|
15. dissolving salt |
|
|
|
16. food rotting |
|
|
|
17. cutting paper |
|
|
|
18. a plant growing |
|
|
|
19. rocket engines burning |
|
|
|
20. dry ice in water |
|
|
Reference for Unit 2, Task 1.5
Introduction: In this activity you will carry out a series of brief experiments. As you perform each experiment, look carefully for clues that indicate whether a chemical reaction has taken place.
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing lab. Handle all chemicals with care as instructed by the teacher.
Dispose of chemicals and solutions in this lab in a waste disposal jar.
Aim: To carry out a series of experiments and record the
observations associated with chemical change.
Apparatus
· water
· filter paper
· ammonium chloride (1 g)
· bunsen burner
· test tube
· watch glass
· copper(II) sulfate solution
· funnel
· iron filings
· ammonium phosphate solution
· silver nitrate solution
· phenolphthalein solution
· calcium hydroxide solution
· eye dropper
Method
1. Obtain 1 g of ammonium chloride. Measure this using a digital scale. Use a piece of paper towel to hold the ammonium chloride sample. Obtain a test tube and add 1.2 cm of water to it. Pour the ammonium chloride into the water and observe and record your observations in regards to sight and touch (outside of test tube). Use the chart that is included in the Observations to record your observations (Chart 1).
2. Obtain 5 mL of copper(II) sulfate solution. Obtain 2 g of iron filings and place the filings in a funnel with filter paper (as instructed by teacher). Use a retort stand and a ring clamp to set up the funnel over a 250 mL beaker. Pour the copper(II) sulfate solution over the iron filings and observe and record the observations in the chart provided (Chart 1).
3. Sprinkle a little table salt on a tarnished penny in a watchglass. Add enough vinegar to cover the coin, and let stand one minute. Wash off and dry the penny. Observe and record its appearance. Use the observation chart provided to record the observations (Chart 1).
4. Obtain a small piece of magnesium ribbon. Light a Bunsen burner according to proper lab procedures and burn the magnesium ribbon using the tongs to hold on to the sample. Do not look directly at burning magnesium. Record your observations in Chart 1.
5. Obtain 1 g of baking soda. Obtain a thumbnail amount of vinegar in a test tube. Put the baking soda into the vinegar. Record your observations in the chart provided (Chart 1).
6. (Teacher Demonstration) Mix 1 mL of sugar and 1 mL of baking soda together. Heat the mixture in a test tube with a supporting test tube/clamp/retort stand. Record the observations in the chart provided.
7. Obtain 2 mL of sodium phosphate solution. Place this in a clean test tube. Make sure that the graduated cylinder is rinsed out after this has been done. Record the appearance of the sodium phosphate solution in Chart 2.
9. Obtain an eye dropper and fill the eye dropper ¼ full with silver nitrate solution. Record the appearance of the silver nitrate in Chart 2.
10. Add the silver nitrate solution, drop by drop, to the sodium phosphate solution. Record the number of drops required to produce a white precipitate (Chart 2). Dispose of the solutions in a waste disposal jar.
11. Obtain 2 mL of phenolphthalein solution. Record the appearance of phenolphthalein (Chart 2). Obtain 2 mL of calcium hydroxide solution. Record the appearance of the calcium hydroxide in the chart provided (Chart 2). Add the two together and record the colour of the precipitate formed (Chart 2). Dispose the waste solutions in a waste disposal jar.
Observations
Chart 1
|
Procedure |
Description of Reactants (What you started with) |
Observations |
Type of Change (Physical or Chemical) |
|
Ammonium chloride + water |
|
|
|
|
Copper(II) sulfate solution + iron filings |
|
|
|
|
Tarnished penny + vinegar + salt |
|
|
|
|
Magnesium ribbon + heat |
|
|
|
|
Baking soda + vinegar |
|
|
|
|
Sugar + Baking Soda + Heat (teacher demonstration) |
|
|
|
Chart 2
|
Solution |
Observations |
|
Sodium phosphate |
|
|
Silver nitrate |
|
|
Sodium phosphate + silver nitrate |
|
|
Phenolphthalein |
|
|
Calcium hydroxide |
|
|
Phenolphthalein + calcium hydroxide |
|
Conclusions
1. In which experiments did a new substance appear to be produced? Give reasons for your answers.
2. What experiment(s) shows a change in temperature?
3. Which experiment(s) showed a change in colour?
4. What is a chemical change? State two examples, one in the lab and one from your everyday experience.
5. Describe 5 clues that may indicate a chemical reaction has occurred.
6. Classify each of the following as a physical or chemical change. Explain your answer in each case.
a. making ice cubes
b. boiling water
c. drawing a sketch
c. baking bread
d. burning coal
e. cutting bread
7. What is a precipitate?
8. How quickly did the precipitates form in this experiment?
9. Identify some of the reactions in this experiment as
a. decomposition
b. synthesis
c. oxidation
Reference to Unit 2, Task 1.6
Introduction: Concept maps show links between a main concept and a variety of specific sub-concepts known as DESCRIPTORS. Descriptors are then linked to term(s) known as CONNECTORS. Connectors are statements which clearly show the link between the descriptors. Concept maps serve as graphic organizers that are covered in class.
Example: Television
|
Signal from cable or antenna |
||
|
|
|

Reference for Unit 2, Task 1.6, 3.1; Unit 4, Task 3.3
Sample Concept Map – Common Chemical Reactions at Home and at Work

Reference for Unit 2, Task 1.6
Student: Date:
Concept:
Organization
___ 1. General to specific
___ 2. Levels of hierarchy shown
___ 3. Branching demonstrated
___ 4. No repetition of descriptors
___ 5. Propositions used for all linkages
___ 6. No linking lines crossed
___ 7. Some cross-linkages between concepts shown
Content
___ 1. Relationships between specific descriptors were logical
___ 2. Appropriate propositions (linkage words) were used
___ 3. Cross linkages were logical
___ 4. Isolated specific descriptors and propositions form a sentence
Reference for Unit 2, Task 1.7
Arranging Reactants and Products in Proper Order
Name:
Date:
reactant: (definition) - ____________________________________________________________
product: (definition) - _____________________________________________________________
Instructions: In a past lab activity (Observing and Recording Chemical Reactions) six experiments were carried out and observations were made with regards to what was started with (reactants), and what was created from these reactants (products). In this activity the reactants and products from this experiment are mixed up. Cut out the Reactants and Products from this chart and paste them into a new chart in correct order.
|
REACTANTS |
PRODUCTS |
|
Baking soda + vinegar |
Heat + light + magnesium oxide |
|
Copper(II) sulfate (aq) + iron filings (s) |
Iron sulfate (aq) + copper (s) |
|
Sugar + baking soda |
Shiny penny + salt + vinegar |
|
Tarnished penny + salt + vinegar |
Heat + light + gas + sugar/baking soda |
|
Magnesium + oxygen |
Ammonium chloride (aq) + water + decrease in temperature |
|
Ammonium chloride(s) + water (aq) |
Baking soda (aq) + vinegar + gas |
|
REACTANTS |
PRODUCTS |
|
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Reference for Unit 2, Task 1.8
Name:
Date:
Factors That Affect Reaction Rates Lab
Introduction: This unit has focussed on the characteristics of chemical reactions. In this lab activity you will observe and record how the reaction rates (how quickly and how slowly a reaction takes place) can be controlled by two specific factors: dilution and surface area.
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Dispose of vinegar and baking soda waste in the drain using excess water.
Aim: To observe and record the effect of dilution,
concentration, surface area, and temperature on the rates of chemical
reactions.
Apparatus
· safety goggles
· Bunsen burner
· grease pencil
· scale
· stopwatch
(Dilution Experiment)
· vinegar
· water
· 4 test tubes
· baking soda
· 50 mL beakers (4)
(Surface Area Experiment)
· powdered carbon
· deflagrating spoon
(Temperature Experiment)
· sugar
· deflagrating spoon
· evaporating dish
Method
The Effect of Dilution [Vinegar/Baking Soda Experiment]
a. Prepare four different dilutions of vinegar in water. In four test tubes, place the following amounts of water and vinegar according to the table:
|
Tube No. |
Volume Water (mL) |
Volume Vinegar (mL) |
Total Volume of Solution (mL) |
Proportion of Vinegar (or Concentration) |
|
1 |
5 |
1 |
6 |
1/6 or 0.17 |
|
2 |
11 |
1 |
12 |
1/12 or 0.083 |
|
3 |
17 |
1 |
18 |
1/18 or 0.055 |
|
4 |
23 |
1 |
24 |
1/24 or 0.042 |
Place a stopper in each test tube and invert it to mix the water and vinegar.
b. Obtain four 50 mL beakers and place 1 g of baking soda in each beaker.
c. Pour the water-vinegar solution from test tube 1 into beaker 1 and observe how long the reactions occurs between the baking soda and the water-vinegar solution. Record your observations and time in the observation chart provided.
d. Repeat with test tubes 2, 3 and 4 and beakers 2, 3, and 4 respectively.
The Effect of Surface Area on Reaction Rates
a. Obtain two 1 g samples of powdered carbon.
b. Set up a Bunsen burner according to lab protocol.
c. Place one of the carbon samples in a deflagrating spoon and heat it in the flame of the Bunsen burner. Record the results in the chart provided.
d. Using a scoopula, lightly sprinkle the other carbon sample into the flame of the Bunsen burner. Record the results in the chart provided.
The Effect of Temperature on Reaction Rates
a. Obtain a small scoop of sugar in a glass evaporating dish.
b. Set up a Bunsen burner according to lab protocol.
c. Observe and record the appearance of the sugar sample as it sits in the evaporating dish.
d. Light the Bunsen burner.
e. Place a small sample of the sugar in the deflagrating spoon and heat the sample in the Bunsen burner flame. Observe and record the observations in the chart provided.
Observations
Dilution Observations
|
Test Tube Number |
Observations |
Total Time for Reaction To Occur (seconds) |
|
1 |
|
|
|
2 |
|
|
|
3 |
|
|
|
4 |
|
|
Surface Area Experiment
|
Test Carried Out |
Observations |
|
Carbon heated in a deflagrating spoon |
|
|
Carbon sprinkled into Bunsen burner flame |
|
Temperature Experiment
|
Test Carried Out |
Observations |
|
Sugar in the evaporating dish |
|
|
Sugar heated in the Bunsen burner flame |
|
Conclusions
1. In the dilution experiment, which test tube had the reaction that lasted the longest time and what was that time?
2. In the dilution experiment, which test tube had the reaction that lasted the shortest time and what was that time?
3. In the dilution experiment, which one of the four test tubes had the strongest concentration of vinegar? Why?
4. Complete the following statements regarding the effect that concentration has on the rate of reaction between vinegar and baking soda. Choose from the following terms:
concentration increased decreased reaction
reactants products increases decreases
a. When the __________ of reactants involved in a chemical ___________ are _____________, the
rate of the reaction increases.
b. When the concentration of reactants is _____________, the rate of the chemical reaction
__________________.
c. Rates of chemical reactions increase when the ____________________of reactants increases.
d. Rates of chemical reactions decrease when the concentration of _______________ decreases.
5. Predict what would happen to a fire if the concentration of oxygen was increased.
6. Why do autobody shops place a freshly painted car in a heated “oven”? Remember that paint drying is a chemical reaction.
7. What sample of carbon reacted more quickly: carbon in a deflagrating spoon or carbon sprinkled into a flame? What factor was changed in this lab procedure?
8. Automobile manufacturers have recently gone to fuel injection rather than gravity-fed carburetors. What have they increased in regards to the fuel being fed into the engine?
9. Sugar is undergoing a chemical reaction in the air as well as when it is placed in the Bunsen burner flame. What is the main difference between these two samples of sugar undergoing a chemical reaction?
Reference for Unit 2, Task 1.11
Oxidation of Paint
Paints are liquids that solidify when they are exposed to air. They are used to cover surfaces for protection and decoration. When paint reacts with air, the process is known as oxidation. Paints are formed by mixing a pigment (the substance that provides the colour) and a binder (a fluid vehicle, such as linseed oil, that solidifies when exposed to air).
The first uses of paint were entirely decorative. These paints lacked a binder (fluid that solidifies when exposed to air). Iron oxide was used for cave paintings about the 15th millenium B.C. In Asia, several pigments made from ores and organic compounds were known about 6000 B.C. Indigo is a pigment extracted from the indigo plant. It was known to the ancient Egyptians, Greeks, Romans, and Inca. Gum arabic, egg white, gelatin, and beeswax were the first materials used to hold these pigments. They could then be spread easily over a surface to be painted. Paints that lacked the modern vehicles (materials to hold the pigments) for creating a hard, bonded coating rapidly degraded over time.
Paints will lose their colour over time due to the same process that made them dry in the first place. Oxygen is a strong oxidizer that combines with substances to form oxides. When a car rusts, it is because of oxygen combining with iron. This process is irreversible. The same thing goes for paint! You might think of a car with faded paint to be experiencing the same process as the metal that rusts on it. The only way to revitalize this paint would be to strip the paint with an oxide remover. Oxide removers can be bought from an auto department store. Many modern car waxes contain oxide removers.
1. What happens when paint is exposed to air?
2. How are paints formed?
3. What is a binder?
4. What was the first paint?
5. List four vehicles for paint that were used in ancient times.
6. Why do paints lose their colour?
7. How is rusting metal and paint that loses its colour the same?
8. Explain how paint that has become oxidized can be revitalized.
Reference for Unit 2, Task 1.11 and 2.11 and Unit 4, Task 3.4
|
Category |
Level 1 (50-59%) |
Level 2 (60-69%) |
Level 3 (70-79%) |
Level 4 (80-100%) |
|
Knowledge (content of presentation – questions answered accurately and completely) |
- has limited understanding of the content, concepts, and/or generalizations in the reading |
- has moderate understanding about the content, concepts, and/or generalizations in the reading |
- shows a largely complete and accurate understanding of the content, concepts, and/or generalizations in the reading |
- thoroughly understands all or almost all content, concepts, and/or generalizations in the reading and demonstrates insightful extensions to some aspects of the information |
|
Communication of Information and Ideas (how ideas are presented – either orally or in visual presentations) |
- communicates information with limited clarity and precision |
- communicates information with moderate clarity and precision |
- communicates information with considerable clarity and precision |
- communicates information with a high degree of clarity and precision |
|
Use of scientific terminology |
- limited use of proper terminology |
- moderate use of proper terminology |
- considerable use of proper terminology |
- high degree of use of proper terminology |
|
Analysing and interpreting the reading |
- requires assistance to locate and interpret information related to a particular question |
- locates and interprets some key information related to a particular question |
- locates and interprets key information related to a particular question and develops concepts related to the question |
- locates and interprets key information related to a particular question and develops the concepts into an insightful new product |
[Parts of this rubric have been developed using the assistance of the Public District School Board Writing Partnership Course Profiles. Science, Grade 9, Academic and Applied, and the Achievement Chart, from The Ontario Curriculum: Science Grades 9 and 10 (1999)]
Note: A student whose achievement is below level 1 (50%) has not met the expectations for this assignment or activity.
Reference for Unit 2, Task 1.12
Name:
Date:
Characteristics of Chemical Reactions
Instructions: Two class periods will be set aside for this final task on Characteristics of Chemical Reactions. There will be 6 lab activities that will be carried out. They are:
1. Lab Safety/Equipment Identification
2. Physical vs. Chemical Change Identification Lab
3. Candle Observation Station
4. Precipitate Experiment (Copper Wire in Silver Nitrate)
5. Baking Soda/Vinegar in a Balloon Experiment
6. Reading for Understanding Assignment (Baking Bread)
Use the instructions provided and the attached observation charts to carry out this final task for this unit.
Station 1: Lab Safety/Equipment Identification
Aim: To correctly identify lab equipment by placing the
correct number beside the corresponding piece of equipment on the list
provided. To correctly match lab safety equipment to their function.
Apparatus
lab and safety equipment
Method/Observations
1. Analyse each piece of equipment provided at this station. Record the correct number beside the corresponding equipment list. There will be no penalty for guessing.
|
Lab Equipment Name |
Number |
|
Beaker tongs |
|
|
Test tube rack |
|
|
Beaker |
|
|
Crucible |
|
|
Erlenmeyer Flask |
|
|
Watch glass |
|
|
Graduated Cylinder |
|
|
Bunsen Burner |
|
|
Mortar and pestle |
|
|
Scoopula |
|
|
Gas Lighter |
|
|
Rubber Stopper |
|
|
Wire Gauze |
|
|
Ring Clamp |
|
|
Funnel |
|
2. Place the correct name of the safety equipment present in the classroom beside its function. The list of the functions is provided.
|
Lab Safety Equipment Name |
Function |
|
|
To wash out the eyes in case of chemical splash or an object hitting the eyes |
|
|
The correct procedure when clothing catches on fire is to “Stop! Drop! Roll!” |
|
|
Used to clean up spills in the lab |
|
|
To put out fires in the lab |
|
|
To protect the eyes while carrying out a lab |
Station 2: Physical Change vs. Chemical Change Lab
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Dispose of chemicals in a waste disposal jar. Handle all chemicals with care as directed by the teacher.
Aim: To observe and record physical and chemical changes.
Apparatus
safety goggles, steel wool, apron, stirring rod, test tube rack, measuring spoon, dilute (less than 0.01M) sodium hydroxide, dilute (less than 0.01M) hydrochloric acid, copper(II) sulfate, magnesium ribbon (2 cm strip), test-tube, stopper, tongs
Method
1. Put on the safety apron provided and the lab goggles.
2. Make a table such as the following:
|
Part |
Name of Substances |
Properties of Starting Substances |
Observations After Mixing |
Physical or Chemical Reaction? |
Evidence |
|
1 |
Water Copper(II) sulfate |
|
|
|
|
~
3. Obtain a small amount of anhydrous copper(II) sulfate in a test tube. Put the test tube in the test tube rack. Obtain some distilled water. Describe the water and the copper(II) sulfate in your table.
4. Pour distilled water into the test tube containing the copper(II) sulfate, to a depth of about 3 cm. Put a stopper on the test tube and seal it. Take the tube out of the rack and mix the contents by turning the tube upside down several times. Return the test tube to the rack.
a. Was there a change? Record the observations in the chart that you created.
b. Make an inference based on your observations: If there was a change, was it physical or chemical. How do you know? Record your inference and the evidence to support it.
1. Pour some of your mixture of copper(II) sulfate from Part 1 of your experiment into a clean, dry, test tube. Leave half of the mixture of copper(II) sulfate for Part 3 of this experiment.
2. Obtain a piece of steel wool.
3. Describe the steel wool. Record your observations in the table.
4. Using a stirring rod, push a small sample of steel wool into the copper(II) sulfate solution. Do not use a large plug of steel wool or it will be impossible to remove it from the test tube.
5. Record your observations in the table. Was there a physical or a chemical change? What is the evidence?
1. Into another clean, dry, test tube pour sodium hydroxide solution to a depth of about 2 cm.
2. Describe the sodium hydroxide solution and the remainder of the copper(II) sulfate mixture.
3. Pour one solution into the other.
4. Record your observations in the table.
5. Was there a physical or a chemical change? What is the evidence?
6. Dispose of the mixtures in the test tubes as instructed by your teacher.
1. Into a clean, dry, test tube pour dilute (less than 0.01M) hydrochloric acid to a depth of about 2 cm. Obtain a small piece of magnesium ribbon.
2. Describe the hydrochloric acid and the magnesium ribbon in the table.
3. Using tongs, carefully add the magnesium ribbon to the test tube.
4. Record your observations in the table.
5. Was there a physical or a chemical change? What is the evidence?
6. Dispose of the mixtures in the test tubes as instructed by your teacher.
Observations
Record all observations in a chart form (see method).
Conclusions
1. What kind of change took place when you mixed the substances in each part of the investigation? What evidence do you have?
2. In a chemical change, the new substance may have a different colour, state, texture, or other property. In each part of this investigation, what properties changed?
Station 3: Candle Observation Lab
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Aim: To observe and record all physical and chemical changes
associated with the burning of a candle.
Apparatus
· matches
· candle
· blank paper for recording the observations (pictorial form/labelled)
Method
1. Light a candle after securing it to a retort stand with a clamp.
2. Use the blank paper to record all physical and chemical changes occurring.
3. Label the diagram to show the characteristics of chemical change occurring. Include the physical changes that are observed as well.
Observations
Draw a labeled diagram of a burning candle.
Conclusions
1. What are the five characteristics of a chemical change?
2. What are two physical changes that are associated with the burning of a candle?
3. What are three characteristics of a chemical change associated with the burning of a candle?
Station 4: Precipitation Experiment
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Dispose of waste in a waste disposal jar.
Aim: To observe and record a precipitation reaction
involving silver nitrate and copper wire.
Apparatus
· 3 mL of silver nitrate solution
· safety goggles
· small piece of copper wire
· test tube
· test tube rack
· small graduated cylinder
Method
1. Obtain 3 mL of silver nitrate solution using the graduated cylinder.
2. Place this solution into a clean, dry, test tube.
3. Obtain a small piece of copper wire.
4. Record your observations of these two substances in the chart provided.
5. Place the small piece of copper wire into the silver nitrate solution.
6. Record the observations of this reaction in chart form.
7. Dispose of the materials according to the instructions from the teacher.
Observations
|
Experimental Step |
Observations |
|
Silver Nitrate Solution |
|
|
Copper Wire |
|
|
Copper Wire + Silver Nitrate Solution |
|
Conclusions
1. What happened when the copper wire was placed into the silver nitrate solution?
2. What colour was the substance that was deposited on the copper wire?
3. Use inference to determine the identity of the substance that was deposited on the copper wire.
4. What is a precipitate?
Station 5: Baking Soda/Vinegar in a Balloon Experiment
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Waste may be disposed of down the drain using excess water.
Aim: To observe and record a gas producing experiment.
Apparatus
· 5 mL dilute (less than 0.01M) acetic acid
· balloon
· 3 g of sodium bicarbonate
· graduated cylinder
· electronic balance
Method
1. Obtain 5 mL of acetic acid in a graduate cylinder.
2. Obtain 3 g of sodium bicarbonate. Measure this amount using the electronic balance.
3. Record the observations of these two substances in the chart provided.
4. Place the baking soda into the balloon.
5. Add the 5 mL of acetic acid into the balloon and quickly tie the balloon up. Record the observations associated with this reaction in the chart provided.
6. Dispose of the balloon and chemicals as instructed by the teacher.
Observations
|
Experimental Step |
Observations |
|
Acetic Acid |
|
|
Sodium Bicarbonate |
|
|
Acetic Acid + Sodium Bicarbonate in the Balloon |
|
Conclusions
1. How did you know that this was or wasn’t a chemical reaction?
2. Explain what happened to the balloon in this experiment.
Lab 6: Reading for Understanding (Baking Bread)
Aim: To read and report on the chemical processes involved in making bread.
Apparatus
· reading excerpt
· worksheet
Method
1. Read the following excerpt. Answer the questions that follow.
How Bread is Made
Making bread involves five basic steps: mixing, kneading, allowing the dough to rise, shaping the bread and baking it. Flour is mixed with yeast, liquid ingredients (usually milk and water) and, any additional ingredients such as salt, sugar, and shortening, to form dough. After the dough becomes too thick to stir, it is kneaded by repeatedly pressing, folding, and turning it to develop and stretch the gluten, which helps the bread rise.
The kneaded dough is allowed to ferment until it rises to double its original size. This doubling in size is due to the carbon dioxide gas produced by the fermentation of sugars, as carried out by the yeast. It is then punched down and kneaded again briefly to break large air pockets into smaller ones and to remix the dough slightly, enabling the yeast to come into contact with any pockets of unmetabolized sugars, and then allowed to rise again. Different types of bread dough may be allowed to rise several times, contributing to the texture and volume of the bread. Before the final rising, the dough is shaped into one of many traditional shapes, for example a loaf or a roll. After the final rising, the bread is baked.
Cooking methods may contribute to the final character of the bread. Heating the dough to temperatures above 60ºC (140ºF) kills the yeast; higher temperatures change the chemical structure of the dough. Most bread is cooked by baking but some breads, such as Chinese dumplings, are steamed, and others, such as Native American fry breads, are fried in oil.
Conclusions
1. What are the five basic steps in making bread:
1. M____________________
2. K____________________
3. R____________________
4. S____________________
5. B____________________
2. What happens to the dough when it becomes too thick to stir? Describe this process.
3. What does ferment mean? You may use a dictionary to find the definition of this chemical process.
Ferment:______________________________________________________________
4. What do yeast cells do when they come into contact with the sugars in the bread dough?
5. What does heating the dough accomplish?
6. The higher temperatures associated with baking bread changes the ____________________ structure
of the bread.
Reference for Unit 2, Task 2.2
Name:
Date:
Sour vs. Bitter Lab Activity
Introduction: Almost everyone has experienced biting into a sour apple or sour grapes. The word “sour” is used to describe a particular taste. This is also where the expression “acid tongue” comes from when used to describe a person who makes sharp remarks. In this lab, foods will be tasted that have “acidic” tastes and “bitter” tastes. These tastes are associated with substances that are ACIDS or BASES. The word acid comes from the Latin word acidus which means sour.
Bases are substances that react with acids to form new products. Many people are familiar with the term “antacid”. Antacids are mild bases! A base has a bitter taste. If you have ever tasted soap, then you have an idea of what a base tastes like.
Safety Precautions
Only taste what the teacher has provided and directed you to taste. Wash your hands thoroughly before starting the lab. Make sure that you dispose of food that has been tasted. Do not share the food that you have tasted with other students. Wash your hands after you have completed the lab.
Aim: To classify seven different foods as either acids or
bases and to record this data in chart form.
Apparatus
Prepared samples of foods (teacher provided)
apple, dill pickles, milk, lemon, tonic water, brussel sprouts, vinegar
Method
1. Obtain a sample of each of the foods listed.
2. Prepare a chart with the headings Sour or Bitter and Acid or Base.
3. Taste each sample and classify it as being sour or bitter. Sour tastes are acids. Bitter tastes are bases.
4. Record the observations.
Observations
|
Food Sample |
Sour or Bitter |
Acid or Base |
|
Apple |
|
|
|
Lemon |
|
|
|
Brussel sprouts |
|
|
|
Dill pickles |
|
|
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Milk |
|
|
|
Tonic water |
|
|
|
Vinegar |
|
|
Conclusions
1. What foods were sour?
2. What foods were bitter?
3. Is taste a good method of identifying acids and bases? Explain. Consider the safety issues involved in your answer.
4. Use the Library/Resource Centre to find out the names of the acids and bases present in each of the samples.
Reference for Unit 2, Task 2.3
Name:
Date:
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Dispose of waste in a waste disposal jar. The only acid used in the touch test is diluted vinegar which contains acetic acid. The only base that is used in the touch test is diluted (less than 0.01M) sodium hydroxide.
Aim: To observe and record the effect of acids (hydrochloric and acetic) and bases (sodium hydroxide and ammonium hydroxide) on red and blue litmus paper, magnesium ribbon, and on a simple touch test.
Apparatus
|
Acid Test |
Base Test |
|
- test tubes (2) |
- test tubes (2) |
|
- glass slide |
- glass stirring rods (2) |
|
- glass stirring rods (2) |
- medicine dropper |
|
- tap water |
- blue and red litmus paper |
|
- magnesium ribbon |
- magnesium ribbon |
|
- blue and red litmus paper |
- (less than 0.01M) sodium hydroxide solution |
|
- dilute vinegar |
- ammonium hydroxide solution |
|
- phenolphthalein indicator |
- tap water |
|
|
- phenolphthalein indicator |
Method
ACID
1. Utilize the data chart shown for your observations on acids
|
Test Material |
Hydrochloric Acid |
Vinegar (diluted) (Contains acetic acid) |
|
Blue Litmus Paper |
|
|
|
Red Litmus Paper |
|
|
|
Phenolphthalein |
|
|
|
Magnesium |
|
|
|
Touch Test |
Not done. |
|
2. Label one test tube #1 and the other #2.
3. Put 4 mL of water into each test tube.
4. Add 15 drops of hydrochloric acid to the first test tube, using the medicine dropper.
5. Add 15 drops of vinegar (contains acetic acid) to the second test tube.
6. Mix the contents of each test tube using a stirring rod.
7. Use the glass rod to add a drop of hydrochloric acid solution to
a. a strip of red litmus paper
b. a strip of blue litmus paper
c. a drop of phenolphthalein indicator on a glass slide
8. Record your results in the above chart.
9. Rinse the glass rod and use it to add a drop of the vinegar (acetic acid) solution to
a. a strip of red litmus paper
b. a strip of blue litmus paper
c. a drop of phenolphthalein indicator on a glass slide
10. Record your results.
11. Place two drops of dilute vinegar (contains acetic acid) on your baby finger with a stirring rod. Describe how it feels.
12. Add a piece of magnesium ribbon to each of the test tubes of hydrochloric acid and vinegar (contains acetic acid). Record your observations.
BASE
1. Record the observations of the base experiment in the following chart:
|
Test Material |
Sodium Hydroxide Solution (diluted) |
Ammonium Hydroxide Solution |
|
Blue Litmus Paper |
|
|
|
Red Litmus Paper |
|
|
|
Phenolphthalein |
|
|
|
Touch Test |
|
Not done |
|
Magnesium |
|
|
2. Label one test tube #1 and the other #2. Put 4 mL of water into each of the two test tubes.
3. Add 15 drops of dilute (less than 0.01M) sodium hydroxide to the first test tube.
4. Add 15 drops of ammonium hydroxide to the second test tube.
5. Stir each of the solutions.
6. Use a glass rod to add a drop of diluted (less than 0.01M) sodium hydroxide to
a. red litmus paper
b. blue litmus paper
c. a drop of phenolphthalein indicator
7. Record your results.
8. Use a glass rod to add a drop of ammonium hydroxide to
a. red litmus paper
b. blue litmus paper
c. a drop of phenolphthalein indicator
9. Record your results.
10. Use a medicine dropper to put two drops of dilute (less than 0.01M) sodium hydroxide solution between two of your fingers. Describe how it feels.
11. Add a piece of magnesium ribbon to each of the dilute (less than 0.01M) sodium hydroxide and ammonium hydroxide solutions
12. Record any observations.
Observations
Record your observations in the chart.
Conclusions
ACIDS
1. List three general properties of an acid.
2. Describe the feeling of an acetic acid solution.
3. What effect does an acid have on a metal?
4. What gas was produced when testing acid in step 11?
5. What test could you carry out to confirm which gas was produced in step 11?
6. In what household product would you find
a. hydrochloric acid
b. acetic acid
BASES
1. List three general properties of a base.
2. Why do all bases possess common properties? (Hint: What do the names of all bases have in common?)
3. Describe the feeling of a sodium hydroxide solution.
4. In which common household products would you find
a. sodium hydroxide
b. ammonium hydroxide
5. Are acids and bases equally dangerous? Explain.
Reference for Unit 2, Task 2.5
Name:
Date:
What is a Chemical Formula?
Instructions: In this activity you will identify the elements in a number of acids and bases, the number of each element in their formula, whether the formula represents an acid or a base, and the common name of each acid or base.
|
Name of Acid |
Formula |
|
Carbonic Acid |
H2CO3 |
|
Hydrochloric Acid |
HC1 |
|
Sulfuric Acid |
H2SO4 |
|
Nitric Acid |
HNO3 |
|
Acetic Acid |
HC2H3O2 |
|
Boric Acid |
H3BO3 |
|
Name of Base |
Formula |
|
Ammonia Water/ammonium hydroxide |
NH4OH |
|
Caustic potash/potassium hydroxide |
KOH |
|
Limewater/calcium hydroxide |
Ca(OH)2 |
|
Lye/sodium hydroxide |
NaOH |
|
Liquid Antacid/magnesium hydroxide |
Mg(OH)2 |
Place the above formulae into the following chart. You may use a Periodic Table to assist you in this exercise.
|
Formula |
Elements Present |
Number of Each Element |
Acid/Base |
Name |
|
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Conclusions
Instructions: Answer the following questions in sentence form.
1. What does every base have in it?
2. What base contains the metal potassium?
3. What does a base do to litmus?
4. How do bases change phenolphthalein?
5. What does a hydroxide consist of?
6. What is the difference between the taste of an acid and the taste of a base?
7. What does an acid do to litmus paper?
8. What is the formula for nitric acid?
9. How do acids change phenolphthalein?
Name:
Date:
Note: Inform your teacher of any food allergies that you have.
Introduction: The strength of an acid or base can be measured using the pH scale. The pH indicates how much acidity is present. The pH scale was named because it represents the “power of hydrogen”. All acids contain hydrogen atoms in combined form. When acids are dissolved in water, they release hydrogen ions (H+ ). Acidity is caused by the presence of these hydrogen ions. The stinging you feel if lemon juice is placed on a cut is due to the H+ ions present. The pH scale has a range from 0 to 14. The closer the pH is to zero, the more acidic it is. The closer the pH of a substance is to 14, the more basic it is. Water has a pH of 7 and is considered to be neutral. The pH of a substance can be determined by using pH paper that is colour coded to the pH scale. pH could also be determined by using a digital pH probe. Use the following pH scale is provided to highlight the pH of some common substances.
Place the following substances on the line provided below by using a ruler and clearly indicating where they sit on the pH scale. Indicate in the chart whether the substance is acidic or basic.
|
Substance |
pH |
Acidic or Basic |
|
Milk |
6.6 |
|
|
Great Lakes Water |
8.0-8.5 |
|
|
Vinegar |
2.2 |
|
|
Neutral Tap Water |
7.0 |
|
|
Lemon Juice |
2.0 |
|
|
Sea Water |
8.3 |
|
|
Ammonia |
11.0 |
|
|
Baking Soda |
8.2 |
|
|
Apples |
3.0 |
|
|
Liquid Antacid |
10.5 |
|
|
Normal Rain |
5.6 |
|
<--------Acidic--------------------------------Neutral--------------------------------------Basic----------->
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Reference for Unit 2, Task 2.7
Name:
Date:
Testing for Acids and Bases in Ten Consumer Products
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Dispose of waste in a waste disposal jar.
Aim: To test ten common consumer products for their acidic or basic properties and to record the observation in chart form.
Apparatus
· medicine dropper
· drain cleaner
· filter papers (10)
· antacid tablet
· toilet bowl cleaner
· lemon juice
· coffee
· vinegar
· liquid stomach antacid
· drain cleaner
· window cleaner
· bleach
· tea
· indicators:
· methyl orange (MO)
· phenolphthalein (P)
· litmus (L)
· bromothymol blue (BTB)
Method
1. Prepare ten pieces of filter paper as shown:

The above diagram refers to the drops of indicator that are used in this experiment:
|
Indicator |
Symbol |
|
Methyl Orange |
MO |
|
Phenolphthalein |
P |
|
Litmus |
L |
|
Bromothymol Blue |
BTB |
2. Place a drop of each indicator to be used at the edge of the paper.
3. Write the name of the indicator below each drop.
4. Write the name of each product being tested in the centre of the piece of filter paper.
5. Allow the filter paper to dry.
6. Use a medicine dropper to add a sample of the product being tested to each indicator.
7. Record the colour changes.
8. Prepare the chart to summarize your results.
Observations
Use this chart to determine if the product contained an acid or a base.
|
Indicator |
Colour
with Acid |
Colour
with Base |
|
Methyl orange |
Red |
Yellow |
|
Litmus |
Red |
Blue |
|
Phenolphthalein |
Colorless |
Pink |
|
Bromothymol blue |
Yellow |
Blue |
|
Product |
Indicator |
Observations |
|
Antacid tablet |
MO L P BTB |
|
|
Toilet bowl indicator |
MO L P BTB |
|
|
Lemon juice |
MO L P BTB |
|
|
Coffee |
MO L P BTB |
|
|
Vinegar |
MO L P BTB |
|
|
Liquid stomach antacid |
MO P L BTB |
|
|
Drain cleaner |
MO P L BTB |
|
|
Window cleaner |
MO P L BTB |
|
|
Bleach |
MO P L BTB |
|
|
Tea |
MO P L BTB |
|
Conclusions
1. What substances are acidic in this lab?
2. What products are basic in this lab?
3. Find out the name(s) of the acid(s) present in each of the products containing acids.
4. Find out the name(s) of the bas(e) present in each of the products containing base.
Reference for Unit 2, Task 2.8
Name:
Date:
pH Determination of Acids and Bases Lab
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after handling.
Dispose of waste in a waste disposal jar.
Aim: To determine the pH of twelve different substances
using universal indicator paper and to classify these substances as acids or
bases.
Apparatus
· universal indicator paper
· 12 test tubes
· orange juice
· grapefruit juice
· milk
· vinegar
· grape juice (yellow)
· calcium hydroxide solution
· ammonia water
· potassium hydroxide
· water
· clear soft drink
· window cleaner
· aspirin
Method
1. Obtain twelve test tubes and label them from 1 - 12.
2. Obtain the twelve substances that are to be tested. Place them in the test tubes according to the following chart:
|
Substance |
Number |
|
orange juice |
1 |
|
grapefruit juice |
2 |
|
milk |
3 |
|
vinegar |
4 |
|
grape juice (yellow) |
5 |
|
calcium hydroxide solution |
6 |
|
ammonia water |
7 |
|
potassium hydroxide |
8 |
|
water |
9 |
|
clear soft drink |
10 |
|
window cleaner |
11 |
|
aspirin |
12 |
3. Use the universal indicator paper to record the pH of the above substances in the chart provided. Indicate if the substance tested is an acid or a base. Refer to the chart on pH for this purpose.
Observations
|
Substance |
pH |
Acidic or Basic |
|
orange juice |
|
|
|
grapefruit juice |
|
|
|
milk |
|
|
|
vinegar |
|
|
|
grape juice (yellow) |
|
|
|
calcium hydroxide solution |
|
|
|
ammonia water |
|
|
|
potassium hydroxide |
|
|
|
water |
|
|
|
clear soft drink |
|
|
|
window cleaner |
|
|
|
aspirin |
|
|
Conclusions
1. What substances were acids?
2. What substances were basic?
3. Why is it important to know if a substance is highly basic or highly acidic?
4. What substance was the strongest acid?
5. What substance was the strongest base?
6. Sequence the substances tested in this lab from the most acidic to the most basic.
Reference for Unit 2, Task 2.9
Name:
Date:
Introduction: In this activity you will observe and record a neutralization reaction. The quantitative method you will use is called a titration.
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Dispose of waste in a waste disposal jar.
Aim: To observe and record the neutralization of an acid.
Apparatus
· evaporating dish
· graduated cylinder
· medicine dropper
· stirring rod
· sodium hydroxide solution
· tap water
· hydrochloric acid solution
· phenolphthalein indicator
· pH paper (universal indicator paper)
Method
1. To find the volume that your medicine dropper will hold, fill the dropper up with water and empty it drop by drop into a graduated cylinder. Continue filling and emptying the dropper until you have placed 100 drops into the graduated cylinder.
2. Read the volume on the cylinder.
3. Calculate the average volume of one drop. An example is as follows:
|
Number of drops |
= 100 |
|
If the volume of the |
|
|
water in the graduated |
|
|
cylinder |
= 10 mL |
|
then, 1 drop of water |
= 10 mL divided by 100 drops |
|
|
= 0.1 mL/drop |
The volume of one drop of water would be 0.1 mL.
4. Empty the graduated cylinder.
5. Measure out 5 mL of hydrochloric acid and pour it into the evaporating dish.
6. Add two drops of phenolphthalein indicator.
7. Record your observations.
8. Rinse your dropper with the sodium hydroxide solution and then fill it with the sodium hydroxide solution.
9. Add sodium hydroxide solution one drop at a time to the solution in the evaporating dish, stirring after each addition.
10. Continue to add sodium hydroxide, keeping track of the number of drops of sodium hydroxide added.
11. Calculate the number of drops of sodium hydroxide needed to make the solution pink.
12. Calculate the volume of sodium hydroxide added. Use the volume per drop that you calculated in step 3.
13. Keep this solution for the next activity.
Observations
Volume of Acid = ________ mL
pH of Acid = _________________
Colour of Acid + phenolphthalein indicator = _____________________
pH of Base = ________
Number of drops of base added to make solution clear = _______________
Volume of base per drop = __________________
Total volume of base added = ___________________________
pH of neutralized/colorless solution = ___________________
Conclusions
1. What was the pH of the acid solution?
2. What was the pH of the base solution?
3. What was the pH of the colorless solution?
4. What do you think is in the antacids that people take to neutralize stomach acid?
5. How did the volume of acid added compare with the volume of base taken?
6. Why was the phenolphthalein indicator added?
7. How would your results change if a more dilute solution of acid than base was used?
Reference for Unit 2, Task 2.10
Name:
Date:
Introduction: In the last task (Task 2.9), it was discovered that acids and bases neutralize each other and produce a product that has a pH of 7.0. In this activity, you will carry out tests that will clearly identify the product of a neutralization reaction.
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Recall the precautions for using a Bunsen burner.
Dispose of waste in a waste disposal jar.
Silver nitrate: Danger! Strong oxidizer. Contact with other materials may cause a fire. Causes skin burns.
Aim: To test, observe, and record the products of a neutralization reaction.
Apparatus
· Neutralized HCl/NaOH solution from activity in Appendix 2.22.
· retort stand
· inoculation loop
· wire gauze
· Bunsen burner
· evaporating dish
· glass slide
· microscope
· eye dropper
· silver nitrate solution
Method
1. Add two drops of the HCl/NaOH neutralized solution to one drop of silver nitrate solution on a glass slide. Observe and record what you see.
2. Place the evaporating dish on a wire gauze and ring clamp attached to a retort stand.
3. Dip an inoculation loop into the solution in the evaporating dish.
4. Hold the loop in a burner flame. Observe the colour of the flame.
5. Heat the solution in the evaporating dish slowly until the solution is almost evaporated.
6. Remove the evaporating dish from the heat and allow it to cool before handling.
7. Describe the residue. Use a microscope to make a diagram of the residue. The residue will be placed on a glass slide.
Observations
|
Test Carried Out |
Observations |
|
HCl/NaOH + Silver Nitrate |
|
|
Flame Test of Neutralized Solution |
|
|
Residue on Evaporating Dish |
|
Conclusions
1. The positive test for sodium (Na) is an orange or yellow flame. What can you conclude about the flame test for the neutralized solution?
2. What ion does silver nitrate test for in step 1?
3. What metal ion was present in the solution?
4. Describe the residue. Name the product that was in this neutralized reaction between NaOH and HCl?
5. If NaCl was produced in the neutralization reaction between NaOH and HCl, what was the other product?
6. Lime is often used to neutralize acid spills. When lime is added to water it forms Ca(OH)2. What products would result if lime was added to a HCl (hydrochloric acid) spill?
Ca(OH)2 + HCl Ü _________ + __________
7. Place the correct salts with the proper neutralization reactions. You may choose from the following four salts: sodium nitrate, ammonium nitrate, ammonium acetate, calcium carbonate
Examples of Neutralization
|
Base |
Acid |
Salt |
Water |
|
Sodium hydroxide + |
Nitric acid → |
|
+ water |
|
Ammonium hydroxide + |
Nitric acid → |
|
+ water |
|
Ammonium hydroxide + |
Acetic acid → |
|
+ water |
|
Calcium hydroxide + |
Carbonic acid → |
|
+ water |
8. You now know:
· neutralization is a chemical change
· neutralization produces a salt, plus water
· salts contain metals (with the exception of ammonium salts)
Reference for Unit 2, Task 2.11
Name:
Date:
Instructions: Read the following Reading for Understanding article and answer the questions in sentence form.
What is Acid Rain?
1. As the name suggests, acid rain is just rain that is acidic. The rain becomes acidic because of gases which dissolve in the rain water to form various acids. Rain is naturally slightly acidic because of the carbon dioxide dissolved in it (which comes from animals breathing). This gives rain a pH of around 6.0, and in some parts of the world it can be as low as 4.0 (This is typical around volcanoes, where the sulphur dioxide and hydrogen sulfide form sulfuric acid in the rain.). The term acid rain is now used to describe rain with a pH below 5.
2. About 70 percent of acid rain comes from sulfur dioxide (SO2), which dissolves into water to form sulfuric acid. The rest comes from various oxides of nitrogen (mainly NO2 and NO3). These gases are produced almost entirely from burning fossil fuels, mainly in power stations and road transport.
3. Acid rain causes damage to lakes and rivers, trees, people, and buildings.
4. Acid rain causes lakes and rivers to become acidic. This kills fish eggs and fish. Short-term increases in acid levels kill a lot of fish, but the greatest threat is from long-term increases, which stops the fish from reproducing. Plants and algae in lakes also suffer from increased acid levels, with numbers dropping off quickly once the pH goes below 5. By the time the pH gets down to 4.5, virtually everything is dead.
5. Trees, especially conifers (trees such as pine and fir that produce cones), are rapidly affected by acid rain. The acid dissolves nutrients the trees need, such as calcium, magnesium, and potassium. The dissolved nutrients are carried away by the rain and the trees starve. The trees are then much more susceptible to other forms of damage, such as being blown down, or breaking under the weight of snow.
6. Surprisingly, the effects of acid rain on trees have overshadowed the effects on people. Many toxic metals are held in the ground in compounds. However, acid rain can break down some of these compounds, freeing the metals and washing them into water sources such as rivers. These toxins, when ingested, represent a serious health hazard to mankind.
7. Lastly, buildings are prone to rapid degradation in the face of acid rain. Limestone and marble is dissolved by acid rain. Worldwide, buildings are experiencing structural damage due to acid rain.
8. The best approach to acid rain is to reduce the amounts of nitrogen oxides and SO2 being released into the environment. Fitting a catalytic converter to a car can reduce emissions of nitrogen oxides by up to 90 percent, but they are very expensive, and cause more carbon dioxide to be released, which contributes to the greenhouse effect.
The following methods represent what you can do to stop acid rain:
· Turn off lights when you leave a room.
· If you have a car, don’t use it for short journeys.
· Ensure that your household is properly insulated.
· Basically, anything at all that uses less energy will help.
Reading for Understanding Questions
Instructions: The Reading for Understanding article on acid rain has eight paragraphs which have been numbered. Use the reference numbers to answer the following questions in complete sentence form.
1. a. What is acid rain?
b. What is the pH of natural rain?
c. What is the pH of acid rain?
d. List the two sources of natural acidity in rain.
2. List the two sources of acid rain for which mankind is responsible.
3. What are the sources of acid rain?
4. What are four things that acid rain damages?
5. List in point form how the following things are damaged by acid rain:
|
Factor Effected by Acid Rain |
Damage Caused by Acid Rain |
|
Lakes and Streams |
|
|
Trees |
|
|
People |
|
|
Buildings |
|
6. How can acid rain be reduced?
Reference for Unit 2, Task 3.1
Name:
Date:
Chemistry in Everyday Life
Aim: To investigate chemical reactions in everyday life.
Lab 1: Tye-dyeing T-shirts
Safety Precautions
Use protective equipment as indicate:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Dispose of waste in a waste disposal jar.
Aim: To investigate the chemical reaction of tye-dyeing.
Materials
· pot of boiling water
· fabric dye (powdered or liquid, available from local grocery or craft stores)
· tongs
· disposable gloves
· white cotton T-shirts
· elastic bands
Caution
Read dye labels carefully. Some dyes are harmful if swallowed.
Method
1. Prewash T-shirts before dyeing. Do not use fabric softener in either the wash or dry cycle.
2. Boil water in pot.
3. When water has boiled, add dye, and stir until completely dissolved. (Read dye label carefully, some dyes may require the addition of salt to water.)
4. To make a circle, put your finger in the centre of one side of the T-shirt and push up to create a handle. Wrap an elastic band over and over again around the handle. Make sure the elastic is tight so the dye does not leak in.
5. When finished, put the t-shirt into the dye.
6. Push the T-shirt down with tongs so that every bit of material is under the dye solution.
7. Leave the T-shirt in until it is one shade darker than what you want, approximately 20 minutes.
8. Take the T-shirt out.
9. Rinse the T-shirt with warm water. Rinse again with cold water to remove any excess dye.
10. Let the T-shirt dry flat.
Questions
1. Why was the T-shirt prewashed?
2. What chemical reaction did you investigate?
3. Why was the T-shirt rinsed several times?
4. Describe your T-shirt when dried.
Lab 2: Yeast
Safety Precautions
Use protective clothing as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Aim: How does yeast cause bread to rise?
Materials
· 75 mL warm (not hot) water
· packet of dry yeast
· pinch of sugar
· 250 mL beaker
Method
1. Open the packet of dry yeast and examine it.
2. Record your observations.
3. Put 75 mL of warm water in a 250 mL beaker. Put pinch of sugar into the beaker with water and stir.
4. Sprinkle the yeast on the water. Do not mix it.
5. Record your immediate observations.
6. Wait 20 minutes and observe what happens to the water/yeast mixture.
7. Record your observations.
Questions
1. Describe what the dry yeast looked like.
2. What happened when the yeast was sprinkled on the water.
3. Describe what happened during the 20 minute observation period.
4. When yeast is wet, water “activates” the yeast. The yeast begins to react with sugar to produce carbon dioxide, a gas.
5. What did you see that supports the statement above?
6. Is carbon dioxide a reactant or product?
Lab 3: Bleaching
Safety Precautions
Use protective equipment as indicated:
· chemical safety goggles
· protective clothing
Wash thoroughly after completing the lab.
Use microamounts of bleach when used. Dispose of waste in a waste disposal jar.
Caution: Safety goggles and gloves must be worn for this
activity. If bleach comes in contact with clothes or skin, rinse immediately
with lots of water.
Aim: To investigate the action of bleach on a variety of fabrics and stains.
Background
The active ingredient in bleach is a substance called sodium hypochlorite (NaClO). The sodium hypochlorite whitens fabrics and removes stains through a reaction called oxidation
Materials
· evaporating dish
· spot plate
· medicine dropper
· household bleach
· a variety of fabrics (e.g., cotton, polyester, rayon, nylon) containing several stains
Method
1. Add 10 drops of bleach to the depression of a spot plate for each stain that is to be tested.
2. Take a sample of stained fabric and record both the colour of the stain and the condition of the fabric before bleaching in a chart similar to the one below.
3. Place each fabric with stain into the bleach in the depression. Record what happens to the colour of the stain.
4. Wait 10 minutes and observe what happens to the fabric.
5. Remove the fabric and rinse.
6. Compare the condition of the fabric after bleaching. Record your observations.
Observations
|
Stain |
Colour of Stain |
Condition of Fabric |
||
|
|
Before |
After |
Before |
After |
|
A |
|
|
|
|
|
B |
|
|
|
|
|
C |
|
|
|
|
|
D |
|
|
|
|
Questions
1. What is the active ingredient in household bleach?
2. What type of reaction lets bleach remove stains?
3. Bleach cannot be used on all fabrics. Why?
4. Of the fabrics tested, which ones were affected by bleach?
5. List the uses of bleach.
6. Bleach reacts with a coloured substance to produce a colourless substance. Name the reactants.
Reference for Unit 2, Task 3.2 and Unit 4, Task 1.5
Name:
Date:
Comic Strip Checklist
Topic:
Check if the assignment includes.
q name, date, and title
q at least four (4) frames
q frames that are at least one-half page in size
q neat drawings
q objects that can be clearly identified by the reader
q q q q q five things circled about chemical reactions/motion
q q q q q one sentence to describe each chemical reaction/motion
Reference for Unit 2, Task 3.3.
Name:
Date:
Classification of Household Products
Fill in the chart using label information.
|
Product |
Substance Found in Product |
Check One. |
Use |
||
|
|
|
Acid |
Base |
Salt |
|
|
Cola |
Phosphoric acid, carbonic acid |
W |
|
|
Drink |
|
Solid Drain Cleaner |
Sodium hydroxide |
|
W |
|
Cleans drains |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Reference for Unit 2, Task 3.4
Name:
Date:
Acids, Bases, or Salts?
Directions
1. Look at each label. For each one:
a. Fill in the product name.
b. Identify the ingredient on the label. Check off the appropriate classification (acid, base or salt).
c. Identify the use of the product.
|
Product |
Substance Found in Product |
Check One |
Use |
||
|
|
|
Acid |
Base |
Salt |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Reference for Unit 2, Task 3.6
Name:
Date:
Careers in Chemistry
1. Name the career chosen.
2. What does the job involve? Describe three things.
3. What does the person need to know about chemistry? Write 2 - 3 sentences.
4. What safety precautions are taken on the job? Write 2 - 3 sentences.
5. What education or training is required for the job?
Reference for Unit 2, Task 3.7, 3.10, and Unit 4, Task 3.2.
This rubric outlines the important components that should be considered when completing the poster and presentation.
|
Category |
Level 1 (50-59%) |
Level 2 (60-69 ) |
Level 3 (70-79%) |
Level 4 (80-100%) |
|
Knowledge
(content of presentation – questions answered accurately and completely) |
- shows a
limited understanding of the content, concepts, and/or generalizations in the
task |
- has some
understanding about the content, concepts, and/or generalizations in the task |
- shows a
largely complete and accurate understanding of the content, concepts, and/or
generalizations in the task |
- thoroughly
understands all content, concepts, and/or generalizations in the tasks and
demonstrates insightful extensions to some aspects of the information |
|
Communication
of Information and Ideas (how ideas are presented – either orally or in the
poster) |
- communicates
information with limited clarity and precision |
- communicates
information with moderate clarity and precision |
- communicates
information with considerable clarity and precision |
- communicates
information with a high degree of clarity and precision |
|
Making
Connections |
- makes
limited understanding of connections to the desired context |
- shows some
understanding of connections to desired context |
- shows
considerable understanding of connections to desired context |
- shows
thorough understanding of connections to desired context |
|
Use of
scientific terminology |
- limited use
of proper terminology |
- moderate use
of proper terminology |
- considerable
use of proper terminology |
- high degree
of use of proper terminology |
|
Creativity |
- limited
imagination shown - story design
is simple |
- some
creativity shown in a story of fair to good design - standard
approach using common resources |
- imaginative
story; well thought out, above the ordinary approach - creative
design and/or materials- good use of available resources |
- a highly
original story or a novel approach - shows
resourcefulness, creativity in design of story |
[Parts of this rubric have been developed using the assistance of
the Public District School Board Writing Partnership Course Profiles. Science,
Grade 9, Academic and Applied, and the Achievement Chart, from The Ontario
Curriculum: Science Grades 9 and 10 (1999)]
Note: A student whose achievement is below level 1 (50%) has not met the expectations for this assignment or activity.
Reference for Unit 2, Task 2.12, 3.10, and Unit 4, Task 3.7.
|
Introduction: Introduce the problem or topic. |
|
Body text paragraph #1: Identify one aspect of the problem or topic. Write at least three sentences about it. |
|
Body text paragraph #2: Identify a second aspect of the problem or topic. Write at least three sentences. |
|
Body text paragraph #3: Identify a third aspect or the problem or topic. Write at least three sentences. |
|
Conclusion: Restate the problem or topic and list the solutions. A personal reflection about the topic may be added in the conclusion. |
Reference for Unit 2, Task 3.10; Unit 4, Task 3.7
(Note: This is a completed sample of Appendix 2.31)
|
Introduction: Introduce the problem or topic. The ozone layer is thinning because
of chemicals that people are releasing into the environment. |
|
Body text paragraph #1: Identify one aspect of the problem or topic. Write at least three sentences about it. The atmosphere is the layer above
the Earth that contains gases. Ozone is found in the atmosphere. It is a
layer of a special type of oxygen that is 15 to 35 km above the surface of
the Earth. The ozone layer is thinning. |
|
Body text paragraph #2: Identify a second aspect of the problem or topic. Write at least three sentences. The main substances that are
thinning the ozone are chlorofluorocarbons or CFCs. When CFCs are released,
they go high up into the atmosphere where ultraviolet rays from the sun break
them down to produce chlorine. The chlorine that is produced will break down
ozone. |
|
Body text paragraph #3: Identify a third aspect or the problem or topic. Write at least three sentences. The biggest hole in the ozone layer
is above the Antarctic. This is because the Antarctic is the coldest spot in
the world. Ice clouds form in very cold places. Sunlight will break down CFCs
in these clouds. The chlorine in these cold areas breaks down ozone faster. |
|
Conclusion: Restate the problem or topic and list the solutions. A personal reflection about the topic may be added in the conclusion. The ozone is thinning because of
CFCs. If countries ban CFCs and other chemicals that break down ozone, it may
be able to repair itself. |
Reference for Unit 2, Task 3.10 and Unit 4, Task 3.7.
These criteria measure research and inquiry skills.
|
Criteria |
Level 1 (50-59%) |
Level 2 (60-69%) |
Level 3 (70-79%) |
Level 4 (80-100%) |
|
Planning: Introduction |
- research topic/problem is stated with limited focus and clarity |
- research topic/problem is stated with moderate focus and clarity |
- research topic/problem is focussed and relevant |
- research topic/problem is clearly stated and focuses on the objectives of the research |
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Communication: Language |
- information may be copied or anecdotal; limited clarity |
- some information is copied, some is written in students own words; some clarity |
- information is written in students own words, moderately clear |
- information is written in students own words; minor errors do not distract reader, clear |
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Recording |
- attempted to record information in one or two Body text paragraphs; may be shorter than three sentences |
-attempted to record information in Body text paragraphs; may be shorter than three sentences |
- has recorded information in most of the Body text paragraphs; uses three sentences |
- has recorded the information in all Body text paragraphs; uses at least three sentences |
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Analysing and Interpreting: Conclusion |
- requires assistance to make conclusions based on content |
- conclusion adequately summarizes the content of the research problem and solution(s); little analysis of the topic is included |
- conclusion restates the research topic/problem and solution(s); reflects some analysis of the topic through personal reflection |
- conclusion is well organized, key concepts are clearly interpreted and content is clearly analysed through insightful personal reflection |
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Resources |
- requires assistance to locate and interpret resources |
- a few relevant resources are used to find simple information |
- a variety of relevant resources are used to find information |
- a wide variety of recent and relevant resources is used to find accurate information |
Note: A student whose achievement is below level 1 (50%) has not met the expectations for this assignment or activity
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